joints = 1 : 3, breadth = 1 : 3. Cephalis hemispherical, with very small
and scarce pores, and a conical horn of the same length. Thorax conical, as
long as broad, with conical papillæ, and eight to ten transverse rows of
roundish pores, gradually increasing in size downwards. Mouth scarcely
constricted, with fifteen to twenty divergent, straight, conical feet, half
as long as the thorax.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.09 long, 0.09
broad.
_Habitat._--North Pacific, Station 244, depth 2900 fathoms.
4. _Anthocyrtium collare_, Haeckel.
_Anthocyrtis collaris_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 64, Taf. vi. fig. 8.
Shell rough, conical, with obliterated collar stricture. Length of the two
joints = 3 : 5, breadth = 4 : 7. Cephalis conical, with a pyramidal horn of
the same length, and with two transverse rows of rather oblong, narrow
pores. Thorax truncate, conical, in the lower part thorny, with six to
eight transverse rows of regular, circular pores, increasing in size
downwards.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.05 long, 0.07
broad.
_Habitat._--Fossil in Barbados.
5. _Anthocyrtium adonis_, n. sp. (Pl. 62 fig. 20).
Shell rough, with sharp collar stricture. Length of the two joints =
3 : 10, breadth = 4 : 12. Cephalis subspherical, with very small circular
pores, and a very long, straight cylindrical, horn, twice to three times as
long as the shell. Thorax inflated, ovate, or subspherical, with small
regular, circular, hexagonally-framed pores. Mouth strongly constricted,
half as broad as the thorax, with fifteen to {1274}twenty divergent, broad,
lamellar, rectangular feet, as long as the thorax, and so densely placed
that their margins come in contact with one another.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.1 long, 0.12 broad.
_Habitat._--Central Pacific, Station 263 to 268, depth 2650 to 3000
fathoms.
6. _Anthocyrtium anemone_, n. sp.
Shell spiny, with sharp collar stricture. Length of the two joints = 1 : 5,
breadth = 1 : 4. Cephalis subspherical, with a conical horn of half the
length, hyaline, without pores. Thorax spiny, pear-shaped, inflated, with
small and numerous, regular, circular pores. Mouth constricted, half as
broad as the thorax, with twelve to fifteen divergent, slender, conical,
denticulate feet, half as long as the thorax.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.14 long, 0.12
broad.
_Habitat._--Tropical Atlantic, Station 347, depth 2250 fathoms; also fossil
in Barbados.
Subgenus 2. _Anthocyrtonium_, Haeckel.
_Definition._--Feet of the peristome-corona parallel, vertical; their basal
and apical distances equal.
7. _Anthocyrtium campanula_, n. sp. (Pl. 62, fig. 17).
Shell smooth, with deep collar stricture. Length of the two joints = 1 : 3,
breadth = 1 : 3. Cephalis spherical, with a conical horn of the same
length. Thorax campanulate, thin-walled, with delicate network of regular,
hexagonal pores and thin bars. Mouth little constricted, with twenty to
twenty-four parallel, vertical, lanceolate feet, about as long as the
cephalis.
_Dimensions._--Cephalis 0.03 diameter, thorax 0.09 long, 0.1 broad.
_Habitat._--South Pacific, Station 302, depth 1450 fathoms.
8. _Anthocyrtium reticulatum_, Haeckel.
_Thyrsocyrtis reticulata_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 84, Taf. xii. fig. 10.
Shell rough, with sharp collar stricture. Length of the two joints = 1 : 2,
breadth = 1 : 3. Cephalis hemispherical, with a prismatic, denticulate horn
of the same length, and small, irregular pores. Thorax campanulate, thorny,
thin-walled, with delicate network of irregular, polygonal pores. Mouth
little constricted, with twelve (or more) small, parallel, vertical,
triangular feet, shorter than the cephalis.
_Dimensions._--Cephalis 0.015 long, 0.02 broad; thorax 0.04 long, 0.06
broad.
_Habitat._--Fossil in Barbados.
{1275}9. _Anthocyrtium leptostylum_, Haeckel.
_Anthocyrtis leptostyla_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 64, Taf. vi. fig. 1.
Shell thorny, with slight collar stricture. Length of the two joints =
1 : 5, breadth = 2 : 4. Cephalis hemispherical, with small, scarce pores
and a slender conical horn of the same length. Thorax spiny, with regular,
circular, quincuncial pores. Mouth constricted, half as broad, with twelve
to eighteen slender, parallel, vertical feet, about as long as the
cephalis.
_Dimensions._--Cephalis 0.02 long, 0.04 broad; thorax 0.1 long, 0.08 broad.
_Habitat._--Central Pacific, Stations 266 to 270, depth 2550 to 2925
fathoms; also fossil in Barbados.
10. _Anthocyrtium hispidum_, Haeckel.
_Anthocyrtis hispida_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 64, Taf. viii. fig. 2.
_Anthocyrtis hispida_, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol.
xxxvi. p. 540, Taf. xxxiii. fig. 30.
Shell thorny, with sharp collar stricture. Length of the two joints =
1 : 4, breadth = 2 : 5. Cephalis hemispherical, hyaline, with few very
small pores, or without any; with a stout conical horn of twice the length.
Thorax spiny, with regular, circular, hexagonally-framed pores (half as
broad as the bars between them). Mouth wide open, scarcely constricted,
with twelve to fifteen parallel, vertical, broad, lamellar, rectangular
feet, reaching nearly the length of the thorax.
_Dimensions._--Cephalis 0.02 to 0.03 long, 0.03 to 0.05 broad; thorax 0.07
to 0.09 long, 0.1 to 0.12 broad.
_Habitat._--Central Pacific, Stations 263 to 265, depth 2650 to 3000
fathoms; also fossil in Barbados.
11. _Anthocyrtium turris_, n. sp.
Shell thorny, very similar to _Calocyclas turris_, Ehrenberg (1875, _loc.
cit._, Taf. xviii. fig. 7), but without fenestrated abdomen. Collar
stricture deep. Length of the two joints = 1 : 3, breadth = 1 : 3. Cephalis
subspherical, hyaline, without pores, with a stout conical horn of twice
the length. Thorax nearly spherical, spiny, with regular, circular,
quincuncial pores. Mouth little constricted, with fifteen to twenty
parallel, vertical, broad, lamellar, rectangular feet, about as long as the
thorax.
_Dimensions._--Cephalis 0.03 long, 0.03 broad; thorax 0.1 long, 0.1 broad.
_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.
{1276}12. _Anthocyrtium doronicum_, n. sp. (Pl. 62, fig. 18).
Shell rough, with sharp collar stricture. Length of the two joints = 1 : 5,
breadth = 1 : 3. Cephalis hemispherical, with small, circular pores and a
stout conical horn of twice the length. Thorax campanulate, subcylindrical,
with regular, circular, quincuncial pores, three to four times as broad as
the bars. Mouth scarcely constricted, with twenty-four to thirty vertical,
nearly parallel, little curved feet, which are about half as long as the
shell, broad, lamellar, rectangular, and in close contact with their edges.
_Dimensions._--Cephalis 0.025 long, 0.035 broad, thorax 0.12 long, 0.1
broad.
_Habitat._--South Pacific, Station 295, depth 1500 fathoms.
Subgenus 3. _Anthocyrturium_, Haeckel.
_Definition._--Feet of the peristome-corona convergent, their basal
distance greater than their apical distance.
13. _Anthocyrtium pyrum_, n. sp. (Pl. 62, fig. 12).
Shell smooth, with obliterated collar stricture. Length of the two joints =
2 : 7, breadth = 3 : 8. Cephalis hemispherical, with a small,
bristle-shaped horn of half the length. Thorax inflated, subglobose, with
regular, circular, quincuncial pores and thin bars. Mouth constricted, only
half as broad, with fifteen to twenty small, triangular, convergent feet,
shorter than the cephalis. (In another specimen the feet were twice as
long, stronger and more convergent, than in the one figured.)
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.07 long, 0.8 broad.
_Habitat._--North Pacific, Station 241, depth 2300 fathoms.
14. _Anthocyrtium setosum_, Haeckel.
_Anthocyrtis setosa_, Haeckel, 1862, Monogr. d. Radiol., p. 311.
? _Lithopera setosa_, Ehrenberg, 1854, Mikrogeol., Taf. xxxv. B., B. iv.
fig. 23.
Shell spiny, with sharp collar stricture. Length of the two joints = 1 : 2,
breadth = 1 : 3. Cephalis hemispherical, with a conical horn of the same
length and some accessory spines. Thorax campanulate, with subregular,
circular pores. Mouth little constricted, with twenty to thirty small,
triangular, convergent feet, about as long as the cephalis. (In Ehrenberg's
incomplete figure they are mostly broken off.)
_Dimensions._--Cephalis 0.02 long, 0.02 broad; thorax 0.04 long, 0.06
broad.
_Habitat._--Tropical Atlantic, Station 347, depth 2250 fathoms.
{1277}15. _Anthocyrtium ehrenbergii_, Haeckel.
_Anthocyrtis ehrenbergii_, Stöhr, 1880, Palæontogr., vol. xxvi. p. 100,
Taf. iii. fig. 21, _a_, _b._
Shell smooth, with obliterated collar stricture. Length of the two joints =
3 : 10, breadth = 2 : 8. Cephalis subcylindrical, with an excentric, stout,
pyramidal horn of the same length. Thorax bottle-shaped, with small,
regular, circular pores of equal size. Mouth little constricted, with
twenty to thirty small, triangular, convergent feet, about half as long as
the cephalis.
_Dimensions._--Cephalis 0.03 long, 0.02 broad; thorax 0.1 long, 0.08 broad.
_Habitat._--Fossil in Tertiary rocks of Sicily (Grotte), Stöhr.
16. _Anthocyrtium zanguebaricum_, Haeckel.
_Anthocyrtis zanguebarica_, Ehrenberg, 1872, Abhandl. d. k. Akad. d.
Wiss. Berlin, p. 285, Taf. ix. fig. 12.
Shell smooth, with slight collar stricture. Length of the two joints =
3 : 10, breadth = 2 : 7. Cephalis subspherical, with an excentric conical
horn of the same length. Thorax slender, ovate or bottle-shaped, with
irregular, roundish pores increasing in size downwards. Mouth little
constricted, with twelve to fifteen small, triangular, convergent feet,
about half as long as the cephalis.
_Dimensions._--Cephalis 0.03 long, 0.02 broad; thorax 0.1 long, 0.07 broad.
_Habitat._--Indian Ocean (Zanzibar), depth 2200 fathoms, Pullen.
17. _Anthocyrtium ficus_, Haeckel.
_Anthocyrtis ficus_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 64, Taf. vi. fig. 3.
Shell rough, with obliterated collar stricture. Length of the two joints =
2 : 12, breadth = 3 : 10. Cephalis conical, with a large, cylindrical horn,
pyramidal at the base, about as long as the thorax. Thorax subovate,
truncate, papillate, with small, regular, circular, quincuncial pores of
the same breadth as the bars. Mouth constricted, two-thirds as broad as the
thorax, with fifteen to twenty strongly convergent, lamellar, rectangular
or sword-shaped feet, nearly as long as the thorax.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.12 long, 0.1 broad.
_Habitat._--Fossil in Barbados.
18. _Anthocyrtium flosculus_, n. sp. (Pl. 62, fig. 19).
_Anthocyrtis flosculus_, Haeckel, 1881, Prodromus et Atlas, pl. lxii.
fig. 19.
Shell ribbed, with distinct collar stricture. Length of the two joints =
1 : 4, breadth = 2 : 4. Cephalis hemispherical, with small, circular pores
and a large cylindrical horn, twice as long as the thorax and half as broad
at the base as the cephalis. Thorax subovate, truncate, with twenty-four to
thirty longitudinal ribs and alternating rows of circular pores. Mouth
constricted, two-thirds {1278}as broad as the thorax, with twenty-four to
thirty slender, convergent feet, which are as long as the entire shell,
with their edges in close contact and their distal ends pointed.
_Dimensions._--Cephalis 0.03 long, 0.05 broad; thorax 0.12 long, 0.12
broad.
_Habitat._--Central Pacific, Stations 265 to 274, depth 2350 to 2925
fathoms.
Genus 568. _Anthocyrtidium_,[185] Haeckel, 1881, Prodromus, p. 431.
_Definition._--#Sethophormida#, (vel Dicyrtida multiradiata aperta) without
thoracic ribs, with numerous (twelve to fifteen or more) subterminal feet,
which are separated from the constricted mouth by a ring of lattice-work.
Cephalis free, with an apical horn.
The genus _Anthocyrtidium_ has been derived from the preceding
_Anthocyrtium_ by further growth and constriction of the peristome, which
becomes separated from the subterminal corona of feet by a more or less
broad ring of lattice-work.
1. _Anthocyrtidium cineraria_, n. sp. (Pl. 62, fig. 16).
Shell campanulate, smooth, with obliterated collar stricture. Length of the
two joints = 5 : 11, breadth = 3 : 13. Cephalis subcylindrical-ovate, with
a conical straight horn of half the length. Thorax hemispherical, inflated,
nearly twice as broad as the constricted mouth. Pores subregular, circular,
double-contoured. Above the mouth, separated from it by two rows of pores,
a corona of twelve to fifteen short conical feet, which are directed
downwards, slightly curved, and as long as the cephalic horn.
_Dimensions._--Cephalis 0.05 long, 0.03 broad; thorax 0.11 long, 0.13
broad.
_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.
2. _Anthocyrtidium ligularia_, n. sp. (Pl. 62, fig. 15).
Shell campanulate, rough, with distinct collar stricture. Length of the two
joints = 1 : 4, breadth = 2 : 6. Cephalis hemispherical, with a slender,
conical, slightly curved horn, about as long as the shell. Thorax
hemispherical, three times as broad as the cephalis, nearly twice as broad
as the constricted mouth, which is prolonged into a prominent smooth ring.
Above the mouth, separated from it by one row of pores, a corona of twelve
to fifteen slender linear feet, which are slightly curved, divergent, and
emarginate at the truncated distal end.
_Dimensions._--Cephalis 0.015 long, 0.03 broad; thorax 0.06 long, 0.09
broad.
_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.
{1279}3. _Anthocyrtidium matricaria_, n. sp.
Shell campanulate, rough, very similar to the preceding species, but
differing in the straight, large, pyramidal horn of the cephalis (as long
as the shell), and in the longer feet, which are twelve to fifteen in
number, little curved at the distal end, pointed, and about as long as the
shell. Length of the two joints = 2 : 6, breadth = 3 : 8. Differs from the
similar _Anthocyrtium centaurea_, Ehrenberg (1875, _loc. cit._, Taf. vi.
fig. 5), mainly in the prominent ring of the peristome.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.06 long, 0.08
broad.
_Habitat._--Fossil in Barbados.
Genus 569. _Carpocanium_,[186] Ehrenberg, 1847, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 54.
_Definition._--#Sethophormida# (vel Dicyrtida multiradiata aperta) without
thoracic ribs, with numerous terminal feet around the mouth (six to twelve
or more). Cephalis hidden in the thorax, without apical horn.
The genus _Carpocanium_, very common, and rich in numerous living and
fossil species, was formerly placed by me among the true Monocyrtida, since
an external constriction is not visible (Monogr., 1862, p. 290). Afterwards
(in 1879) Richard Hertwig demonstrated that the cavity of the ovate shell,
externally simple, is divided by an internal transverse septum into two
joints, the upper of which is the flat rudimentary cephalis (Organism. d.
Radiol., p. 79; compare also Bütschli, 1882, _loc. cit._, p. 535). Indeed
this septum, with four central crossed cortinar beams, is a true collar
septum, and _Carpocanium_ has been derived from _Anthocyrtis_ or
_Desmospyris_ by reduction of the cephalis, which is very flat and
perfectly hidden in the uppermost part of the thorax. The apical horn is
lost. If the internal septum were to become lost, the genus would pass over
into _Carpocanistrum_.
Subgenus 1. _Carpocanarium_, Haeckel.
_Definition._--Peristome-corona composed of six feet (three primary
perradial alternating with three secondary interradial).
1. _Carpocanium calycodes_, Stöhr.
_Carpocanium calycodes_, Stöhr, 1880, Palæontogr., vol. xxvi. p. 96, Taf.
iii. fig. 8.
Shell urceolate, smooth, nearly twice as long as broad, with hemispherical
vaulted cephalis. Length of the two joints = 3 : 16, breadth = 5 : 10.
Pores regular, circular, as broad as the bars, {1280}quincuncially disposed
in about five longitudinal series at each side. Mouth constricted, half as
broad as the thorax. Peristome with six vertical, equilateral, triangular
feet.
_Dimensions._--Cephalis 0.015 long, 0.025 broad; thorax 0.08 long, 0.05
broad.
_Habitat._--Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).
2. _Carpocanium setosum_, Haeckel.
_Halicalyptra setosa_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 160, Taf. ii. fig. 12.
Shell ovate, truncate at the mouth, thorny, exactly as long as broad.
Length of the two joints = 1 : 8, breadth = 3 : 9. Cephalis hidden, with
very small pores. Thorax inflated, with regular, circular pores, twice as
broad as the bars, in about ten longitudinal series at each side. Mouth
constricted, half as broad as the thorax. Peristome with six vertical,
parallel, broad, lamellar, rectangular feet, separated by equal internals,
half as long as the shell.
_Dimensions._--Cephalis 0.01 long, 0.03 broad; thorax 0.08 long, 0.09
broad.
_Habitat._--Fossil in Barbados.
3. _Carpocanium laeve_, Ehrenberg.
_Carpocanium laeve_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 287.
Shell subspherical, smooth, equal in length and breadth, with little
vaulted, cap-shaped cephalis. Length of the two joints = 1 : 6, breadth =
4 : 7. Pores regular, circular, twice as broad as the bars, in nine
longitudinal rows. Mouth constricted, only one-third as broad as the
thorax. Peristome with six strong conical feet, which are slightly curved
and convergent.
_Dimensions._--Cephalis 0.01 long, 0.04 broad; thorax 0.06 long, 0.07
broad.
_Habitat._--Mediterranean (Greece); Tropical Atlantic, Station 348, depth
2450 fathoms.
4. _Carpocanium lanceolatum_, n. sp.
Shell subspherical, thorny, with perfectly hidden cephalis. Length of the
two joints = 1 : 3, breadth = 1 : 3. Pores regular, circular, hexagonally
framed, half as broad as the bars, in about sixteen longitudinal rows at
each side. Mouth constricted, half as broad as the thorax. Peristome with
six large lanceolate, vertical, lamellar feet, half as long as the shell.
_Dimensions._--Cephalis 0.03 long, 0.03 broad; thorax 0.09 long, 0.09
broad.
_Habitat._--South Pacific, Station 300, depth 1375 fathoms.
Subgenus 2. _Carpocanidium_, Haeckel.
_Definition._--Peristome-corona composed of nine feet (three primary
perradial and six secondary interradial).
{1281}5. _Carpocanium diadema_, Haeckel.
_Carpocanium diadema_, Haeckel, 1862, Monogr. d. Radiol., p. 290, Taf. v.
fig. 1.
_Carpocanium diadema_, R. Hertwig, 1879, Organism. d. Radiol., p. 79,
Taf. viii. figs. 7, 7_a_, 8, 8_a_, 8_b_.
Shell ovate, with little vaulted cephalis. Length of the two joints =
1 : 8, breadth = 3 : 6. Pores regular, circular, in about twelve
longitudinal rows, twice as broad as the bars. Mouth constricted, half as
broad as the thorax. Peristome with nine vertical, equilateral, triangular
feet.
_Dimensions._--Cephalis 0.01 long, 0.03 broad; thorax 0.08 long, 0.06
broad.
_Habitat._--Cosmopolitan; Mediterranean, Atlantic, Indian, Pacific; many
stations, surface.
6. _Carpocanium cylindricum_, n. sp.
Shell cylindrical, with hemispherical, flatly vaulted cephalis. Length of
the two joints = 1 : 4, breadth = 3 : 3. Pores regular, circular,
double-contoured, as broad as the bars, in about fifteen longitudinal
series. Mouth constricted, two-thirds as broad as the thorax. Peristome
with nine vertical, slender, triangular, pointed feet.
_Dimensions._--Cephalis 0.02 long, 0.06 broad; thorax 0.08 long, 0.06
broad.
_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.
7. _Carpocanium enneaphyllum_, n. sp.
Shell slenderly ovate, at the mouth truncate, thorny, with hemispherical,
vaulted cephalis. Length of the two joints = 1 : 6, breadth = 2 : 4. Pores
regular, circular, hexagonally framed, as broad as the bars, in about
thirteen longitudinal rows. Mouth constricted, about two-thirds as broad as
the thorax. Peristome with nine broad, lamellar, vertical, nearly square
feet, half as long as the shell, with small intervals.
_Dimensions._--Cephalis 0.02 long, 0.04 broad; thorax 0.12 long, 0.09
broad.
_Habitat._--South Atlantic, Station 332, depth 2200 fathoms.
8. _Carpocanium solitarium_, Ehrenberg.
_Carpocanium solarium_, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 28.
_Lithocampe solitaria_, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad.
d. Wiss. Berlin, p. 65.
Shell slenderly ovate, twice as long as broad, with hidden spherical
cephalis, completely enclosed in the summit of the thorax. Length of the
two joints = 1 : 6, breadth = 1 : 4. Pores small, regular, circular, as
broad as the bars, in about eleven longitudinal rows. Mouth gradually
constricted, half as broad as the thorax. Peristome with nine ovate blunt
feet, which are as long as the cephalis, little curved and convergent.
_Dimensions._--Cephalis 0.02 long, 0.02 broad; thorax 0.12 long, 0.07
broad.
_Habitat._--Fossil in Tertiary rocks of Sicily (Caltanisetta).
{1282}9. _Carpocanium gemmula_, n. sp.
Shell subspherical, smooth, equal in length and breadth, with hemispherical
vaulted cephalis. Length of the two joints = 2 : 7, breadth = 4 : 9. Pores
small, regular, circular, twice as broad as the bars, in about twenty
longitudinal rows. Mouth strongly constricted, only one-fourth as broad as
the thorax. Peristome with nine conical feet, which are twice as long as
the cephalis, curved, and so convergent that their distal ends come nearly
in contact.
_Dimensions._--Cephalis 0.02 long, 0.04 broad; thorax 0.07 long, 0.09
broad.
_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.
10. _Carpocanium microdon_, Ehrenberg.
_Carpocanium microdon_, Ehrenberg, 1858, Monatsber. d. k. preuss. Akad.
d. Wiss. Berlin, p. 30.
Shell broad, ovate, rough, with perfectly hidden cephalis. Length of the
two joints = 2 : 9, breadth = 4 : 7. Pores very small and scarce, smaller
than the bars between them, irregularly scattered. Mouth constricted,
one-third as broad as the thorax. Peristome with nine short, triangular,
pointed, convergent feet.
_Dimensions._--Cephalis 0.02 long, 0.04 broad; thorax 0.09 long, 0.07
broad.
_Habitat._--Mediterranean (Crete), Atlantic (Canary Islands), Station 354,
surface.
Subgenus 3. _Carpocanobium_, Haeckel.
_Definition._--Peristome-corona composed of twelve or more feet.
11. _Carpocanium trepanium_, n. sp. (Pl. 52, fig. 18).
Shell subcylindrical, with flatly vaulted cephalis. Length of the two
joints = 1 : 6, breadth = 3 : 4. Pores regular, hexagonal, four to six
times as broad as the bars. Mouth little constricted, two-thirds as broad
as the thorax. Peristome with eighteen to twenty-four large, slender,
triangular, vertical feet.
_Dimensions._--Cephalis 0.02 long, 0.06 broad; thorax 0.12 long, 0.08
broad.
_Habitat._--Indian Ocean, Madagascar (Rabbe), surface.
12. _Carpocanium hexagonale_, n. sp. (Pl. 52, fig. 15).
Shell broadly ovate or subconical, with vaulted, cap-shaped cephalis.
Length of the two joints = 2 : 7, breadth = 6 : 9. Thorax subglobular,
truncate. Pores subregular, hexagonal, three to four times as broad as the
bars. Mouth constricted, two-thirds as broad as the thorax. Peristome with
twenty to twenty-five small, triangular, vertical feet.
_Dimensions._--Cephalis 0.02 long, 0.05 broad; thorax 0.07 long, 0.09
broad.
_Habitat._--Tropical Atlantic, Station 347, surface.
{1283}13. _Carpocanium petalospyris_, n. sp. (Pl. 52, fig. 19).
Shell subspherical, smooth, with perfectly hidden cephalis. Length of the
two joints = 1 : 6, breadth = 3 : 6. Pores regular, circular, hexagonally
framed, twice as broad as the bars, in about sixteen longitudinal rows.
Mouth slightly constricted, little narrower than the thorax. Peristome with
twenty to twenty-four vertical, broad, lamellar feet, which are nearly as
long as the shell, at the distal end truncate, and almost in contact at
their edges.
_Dimensions_.--Cephalis 0.02 long, 0.05 broad; thorax 0.11 long, 0.12
broad.
_Habitat_.--Central Pacific, Station 271, depth 2425 fathoms.
14. _Carpocanium polypterum_, Haeckel.
_Cryptoprora polyptera_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 287, Taf. ix. fig. 17.
_Carpocanium macropterum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 302.
Shell campanulate-conical, smooth, with perfectly hidden cephalis. Length
of the two joints = 1 : 6, breadth = 4 : 6. Pores regular, circular, twice
as broad as the bars, in about sixteen longitudinal rows. Mouth wide open,
not constricted. Peristome with twenty to thirty vertical, slender, conical
feet, about as long as the shell.
_Dimensions_.--Cephalis 0.01 long, 0.04 broad; thorax 0.06 long, 0.06
broad.
_Habitat_.--Indian Ocean (Zanzibar), depth 2200 fathoms (Pullen).
15. _Carpocanium palmipes_, n. sp.
Shell ovate, very thick-walled, smooth. Lower half of the subspherical
cephalis hidden in the summit of the thorax, upper half free, with few
small pores. Length of the two joints = 3 : 10, breadth = 3 : 10. Thorax
foveolate, with oblong dimples, each of which encloses a small, circular,
double-contoured pore, half as broad as the bars. Mouth little constricted,
nearly as broad as the thorax. Peristome prolonged into a solid,
cylindrical tube, nearly as long and as broad as the shell; the upper half
of the tube is solid, the lower divided into from twelve to fifteen
vertical, lamellar, pointed feet.
_Dimensions_.--Cephalis 0.03 long, 0.03 broad; thorax 0.1 long, 0.1 broad.
_Habitat_.--Western Tropical Pacific, Station 225, depth 4475 fathoms.
16. _Carpocanium peristomium_, n. sp. (Pl. 52, figs. 16, 17).
Shell ovate, smooth, with perfectly hidden, flat cephalis (fig. 17). Length
of the two joints = 2 : 10, breadth = 5 : 9. Pores small and very numerous,
regular, circular, as broad as the bars, in about twenty longitudinal rows.
Mouth little constricted. Peristome broad; in the upper {1284}half a
hyaline, circular ring, in the lower half divided into from eighteen to
twenty-four triangular, curved, little convergent feet.
_Dimensions._--Cephalis 0.02 long, 0.05 broad; thorax 0.1 long, 0.09 broad.
_Habitat._--Cosmopolitan; Atlantic, Indian, Pacific; many stations, at
various depths.
17. _Carpocanium coronatum_, Ehrenberg.
_Carpocanium coronatum_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 66, Taf. v. fig. 7.
Shell ovate, smooth, with perfectly hidden, subspherical cephalis. Length
of the two joints = 2 : 9, breadth = 2 : 8. Pores small and very numerous,
twice as broad as the bars, regular, circular, in about twenty longitudinal
rows. Mouth little constricted, two-thirds as broad as the thorax.
Peristome with twenty-five to thirty short, bristle-shaped feet, which are
slightly curved, convergent, and in the upper half connected by a solid
ring.
_Dimensions._--Cephalis 0.02 long, 0.02 broad; thorax 0.09 long, 0.08
broad.
_Habitat._--Fossil in Barbados.
18. _Carpocanium dactylus_, n. sp.
Shell slenderly ovate, twice as long as broad, with flat, perfectly hidden
cephalis. Length of the two joints = 1 : 12, breadth = 4 : 8. Pores
subregular, circular, as broad as the bars, in about twelve longitudinal
rows, separated by prominent longitudinal ribs. Mouth constricted,
two-thirds as broad as the thorax. Peristome with twelve large, lanceolate,
lamellar, convergent feet.
_Dimensions._--Cephalis 0.01 long, 0.04 broad; thorax 0.12 long, 0.08
broad.
_Habitat._--South Pacific, Station 295, depth 1500 fathoms.
19. _Carpocanium irregulare_, n. sp. (Pl. 52, fig. 14).
Shell irregular, roundish, subovate, with flat and oblique, perfectly
hidden cephalis. Length of the two joints = 1 : 10, breadth = 3 : 9. Pores
irregularly scattered, roundish, about as broad as the bars. Mouth wide
open, not at all or little constricted. Peristome with twenty to thirty
long, lamellar, pointed feet, which are irregularly curved and convergent.
_Dimensions._--Cephalis 0.01 to 0.02 long, 0.03 to 0.04 broad; thorax 0.09
to 0.11 long, 0.08 to 0.09 broad.
_Habitat._--Central Pacific, Station 263 to 274, surface, and at various
depths.
20. _Carpocanium verecundum_, n. sp. (Pl. 52, figs. 12, 13).
Shell ovate, smooth, with flat, perfectly hidden cephalis (fig. 12). Length
of the two joints = 1 : 9, breadth = 4 : 9. Pores subregular, circular,
twice as broad as the bars, in about eighteen, {1285}partly interrupted,
longitudinal rows, separated by prominent crests. Mouth little constricted.
Peristome with twenty to twenty-four broad, lamellar, pointed feet, which
are about as long as the shell, little curved, and convergent.
_Dimensions._--Cephalis 0.01 long, 0.04 broad; thorax 0.09 long, 0.09
broad.
_Habitat._--North Pacific, Station 244, depth 2900 fathoms.
21. _Carpocanium virgineum_, n. sp. (Pl. 52, fig. 20).
Shell ovate, smooth, with flat perfectly hidden cephalis. Length of the two
joints = 1 : 8, breadth = 3 : 9. Pores regular, circular, hexagonally
framed, as broad as the bars, in about sixteen longitudinal rows on each
side. Mouth little constricted. Peristome with eighteen to twenty-four very
large, lamellar, pointed feet, which are longer than the shell, and so
curved and convergent that their distal points come nearly in contact.
_Dimensions._--Cephalis 0.01 long, 0.03 broad; thorax 0.08 long, 0.09
broad.
_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.
Subfamily 2. SETHOPHÆNIDA, Haeckel, 1881, Prodromus, p. 433.
_Definition._--#Anthocyrtida# with the basal mouth of the shell fenestrated
(vel Dicyrtida multiradiata clausa).
Genus 570. _Sethophæna_,[187] Haeckel, 1881, Prodromus, p. 433.
_Definition._--#Sethophænida# (vel Dicyrtida multiradiata clausa) with
lateral apophyses. Cephalis with a horn.
The genus _Sethophæna_ and the following _Clistophæna_ form together the
small subfamily of Sethophænida, comprising those Dicyrtida in which the
thorax bears numerous radial appendages (four to six or more), and the
mouth is closed by a lattice-plate. In _Sethophæna_ the apophyses are
lateral wings, as in _Micromelissa_, from which it may be derived by
development of secondary wings, interpolated between the three primary
wings.
1. _Sethophæna tetraptera_, n. sp.
Shell smooth, with deep collar stricture. Length of the two joints =
3 : 10, breadth = 4 : 9. Cephalis subspherical, without horn. Thorax ovate,
with rounded hemispherical base, and subregular, hexagonal pores. From its
upper half (below the collar stricture) arise four divergent,
{1286}conical, straight wings, of half the length, opposite in pairs in two
meridional planes, perpendicular to one another (compare _Tetralacorys_,
Pl. 65, figs. 4, 5).
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.1 long, 0.09 broad.
_Habitat._--South Pacific, Station 300, depth 1375 fathoms.
2. _Sethophæna hexaptera_, n. sp. (Pl. 97, fig. 13).
Shell rough, pear-shaped, with distinct collar stricture. Length of the two
joints = 1 : 4, breadth = 2 : 4. Cephalis hemispherical, with a conical
horn of the same length. Thorax inflate, inversely ovate, nearly
pear-shaped, with subregular, circular pores. From its upper half arise, by
a broad base, six divergent, strong, conical wings, which are horn-like,
curved downwards, and half as long as the thorax.
_Dimensions._--Cephalis 0.025 long, 0.04 broad; thorax 0.09 long, 0.08
broad.
_Habitat._--Central Pacific, Station 268, depth 2900 fathoms.
3. _Sethophæna enneaptera_, n. sp.
Shell rough, with sharp collar stricture. Length of the two joints = 1 : 6,
breadth = 1 : 3. Cephalis subspherical, with a stout conical horn of twice
the length. Thorax inversely ovate, with pointed, conical, basal part, and
irregular, roundish pores. From its middle part arise, by a broad
triangular base, nine compressed, divergent wings, which are a little
curved, slender, and about as long as the thorax.
_Dimensions._--Cephalis 0.025 long, 0.03 broad; thorax 0.17 long, 0.1
broad.
_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.
4. _Sethophæna polyptera_, n. sp.
Shell thorny, with slight collar stricture. Length of the two joints =
1 : 10, breadth = 3 : 8. Cephalis flat, cap-shaped, without horn. Thorax
pear-shaped, with hemispherical base and regular, circular pores. From its
lower half (beyond the equator) arises a corona of numerous short conical
wings (eighteen to twenty-four), which are a little curved, and divergent
downwards, scarcely one-third as long as the thorax.
_Dimensions._--Cephalis 0.015 long, 0.04 broad; thorax 0.15 long, 0.12
broad.
_Habitat._--North Pacific, Station 253, depth 3125 fathoms.
Genus 571. _Clistophæna_,[188] Haeckel, 1881, Prodromus, p. 433.
_Definition._--#Sethophænida# (vel Dicyrtida multiradiata clausa) with
terminal apophyses. Cephalis with a horn.
{1287}The genus _Clistophæna_ agrees with the preceding _Sethophæna_ in the
mouth of the thorax being closed by a lattice-plate. But the appendages of
the thorax are terminal feet, not lateral wings; their number is commonly
six or nine, rarely more. _Clistophæna_ may be derived either from
_Tetrahedrina_ by interpolation of secondary feet between the three
primary, or from _Sethamphora_ by development of a basal lattice-plate
closing the mouth.
1. _Clistophæna rüstiana_, n. sp. (Pl. 57, fig. 6).
Shell rough, with distinct collar stricture. Length of the two joints =
3 : 10, breadth = 4 : 11. Cephalis hemispherical, with small, circular
pores and a stout oblique horn three times the length, which is three-sided
prismatic, and at the top denticulate. Thorax subconical, inflate, with
regular, circular, quincuncial pores, increasing in size towards the base.
Margin of the flat base, with six divergent, stout feet of the same
prismatic form as the cephalic horn, with denticulate distal ends, about as
long as the thorax. This elegant species is dedicated to Dr. Rüst of
Freiburg, the discoverer of numerous fossil Radiolaria in the Liassic and
Jurassic formations.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.1 long, 0.11 broad.
_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.
2. _Clistophæna hexolena_, n. sp.
Shell smooth, with slight collar stricture. Length of the two joints =
1 : 4, breadth = 1 : 5. Cephalis subspherical, small, with a large,
vertical, cylindrical horn, about as long as the shell, and small, circular
pores. Thorax nearly three-sided pyramidal or tetrahedral, with three
rounded edges and sub-regular, circular pores. Margin of the flat base with
six conical, divergent, straight feet, somewhat shorter than the thorax.
(Three on the corners, one on the middle of each side of the triangular
base.)
_Dimensions._--Cephalis 0.03 diameter, thorax 0.12 long, 0.14 broad.
_Habitat._--North Pacific, Station 241, depth 2300 fathoms.
3. _Clistophæna pyramidalis_, n. sp.
Shell smooth, with slight collar stricture. Length of the two joints =
2 : 8, breadth = 3 : 10. Cephalis hemispherical, with a stout pyramidal
horn of twice the length. Thorax six-sided pyramidal, with regular,
circular pores of equal size, and six prominent, straight edges, which are
prolonged into six divergent, pyramidal feet of half the length.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.08 long, 0.1 broad.
_Habitat._--Central Pacific, Station 274, depth 2750 fathoms.
{1288}4. _Clistophæna armata_, n. sp. (Pl. 57, fig. 7).
Shell spiny, with deep collar stricture. Length of the two joints = 4 : 18,
breadth = 5 : 15. Cephalis subspherical, with small, circular,
hexagonally-framed pores, and a stout, three-sided prismatic, cuspidate
horn of the same length. Thorax pear-shaped, with regular, circular pores
and three pairs of stout pyramidal wings, placed in the three primary
meridional planes of the collar beams; three of them lie in the upper, and
three in the lower third of the thorax. Margin of the flat base with nine
cylindrical, somewhat club-shaped, divergent feet.
_Dimensions._--Cephalis 0.04 long, 0.05 broad; thorax 0.18 long, 0.15
broad.
_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.
5. _Clistophæna enneolena_, n. sp.
Shell spiny, with sharp collar stricture. Length of the two joints =
4 : 20, breadth 5 : 16. Cephalis hemispherical, hyaline, with a stout
conical horn of the same length and some small accessory horns. Thorax
ovate, spiny, with subregular, circular pores. Margin of the vaulted base
with nine divergent, conical feet, half as long as the thorax.
_Dimensions._--Cephalis 0.04 long, 0.05 broad; thorax 0.2 long, 0.16 broad.
_Habitat._--South Pacific, Station 296, depth 1825 fathoms.
6. _Clistophæna polyolena_, n. sp.
Shell smooth, conical, with obliterated collar stricture. Length of the two
joints = 1 : 5, breadth = 2 : 5. Cephalis hemispherical, with small,
circular pores and two divergent conical horns (a major occipital and a
smaller frontal horn). Thorax obtusely conical, with regular, hexagonal
pores at the mantle, and circular pores in the basal plate, the margin of
which bears eighteen vertical, parallel, conical feet, as long as the
cephalis.
_Dimensions._--Cephalis 0.015 long, 0.025 broad; thorax 0.08 long, 0.08
broad.
_Habitat._--Central Pacific, Stations 271 to 274, depth 2350 to 2750
fathoms.
Family LXIV.--#SETHOCYRTIDA#, n. fam.
_Sethocorida et Sethocapsida_, Haeckel, 1881, Prodromus, pp. 439, 433.
_Definition._--#Dicyrtida# eradiata. (#Cyrtoidea# with a two-jointed shell,
divided by a transverse constriction into cephalis and thorax, without
radial apophyses).
The family #Sethocyrtida#, composed of the Sethocorida and Sethocapsida of
my Prodromus, comprises those #Cyrtoidea# in which the shell is two-jointed
and bears no radial apophyses. The two subfamilies differ in the shape of
the mouth, which in the Sethocorida is a simple wide opening, and in the
Sethocapsida is closed by a lattice-plate. The former are here divided into
eight, the latter into three genera.
{1289}Numerous living and fossil forms of Sethocyrtida were previously
described by Ehrenberg, partly in his genera _Dictyocephalus_ and
_Lophophæna_, partly (intermingled with three-jointed and many-jointed
forms) in the genera _Eucyrtidium_ and _Lithocampe_. A larger number of new
forms has been found in the Radiolarian ooze collected by the Challenger,
and others fossil in Barbados. Many of these Sethocyrtida are common and
widely distributed. When a new third joint is formed on their basal mouth,
they pass over into Theocyrtida.
The cephalis is usually subspherical or hemispherical, and much smaller
than the thorax, the form of which exhibits all possible intermediate
stages between flat, discoidal, conical, cylindrical, and ovate forms. The
wide open mouth becomes more and more constricted, and finally closed in
the Sethocapsida. The majority of the Sethocyrtida may have been derived
either from the Tripocyrtida, or from the Anthocyrtida by reduction and
loss of the radial apophyses.
_Synopsis of the Genera of Sethocyrtida._
-------------------------------------------------------------------------
I. Subfamily Sethocorida.
Terminal mouth of the thorax a simple wide opening.
--------------------
Thorax conical or campanulate, gradually dilated.
-------------------------------------------------------------------------
Shell simple, without mantle, 572. _Sethoconus_.
Shell double, with an arachnoid mantle, 573. _Periarachnium_.
-------------------------------------------------------------------------
Thorax discoidal, flatly expanded.
-------------------------------------------------------------------------
Cephalis very large, without horn, 574. _Sethocephalus_.
{ Mouth simple, 575. _Sethocyrtis_.
Cephalis with a single horn. {
{ Mouth tubular, 576. _Sethocorys_.
-------------------------------------------------------------------------
Thorax cylindrical or ovate, with truncate, constricted or tubular mouth.
-------------------------------------------------------------------------
Cephalis with two horns or a bunch of horns, 577. _Lophophæna_.
Cephalis without horn, 578. _Dictyocephalus_.
-------------------------------------------------------------------------
II. Subfamily Sethocapsida.
Terminal mouth closed by a lattice-plate.
--------------------
Cephalis free, not hidden in the thorax
-------------------------------------------------------------------------
One horn, 579. _Sethocapsa_.
No horn, 580. _Dicolocapsa_.
-------------------------------------------------------------------------
Cephalis hidden in the upper part of the thorax.
-------------------------------------------------------------------------
No horn, 581. _Cryptocapsa_.
Subfamily 1. SETHOCORIDA, Haeckel, Prodromus, p. 430.
_Definition._--#Sethocyrtida# with the basal mouth of the shell open (vel
Dicyrtida eradiata aperta).
{1290}Genus 572. _Sethoconus_,[189] Haeckel, 1881, Prodromus, p. 430.
_Definition._--#Sethocorida# (vel Dicyrtida eradiata aperta) with conical
or campanulate, gradually dilated thorax and wide open mouth. Cephalis with
one or more horns.
The genus _Sethoconus_ is the oldest and simplest form of the Sethocorida,
or of those Dicyrtida in which the simple thorax bears no apophyses and has
the mouth open and not closed by a basal lattice-plate. Probably all those
eradiate Sethocorida have been derived either from triradiate Sethopilida
(_Lychnocanium_), or from multiradiate Sethophormida (_Sethophormis_,
_Anthocyrtis_ ?) by loss of the radial ribs and feet. In _Sethoconus_ the
thorax is more or less conical, sometimes more campanulate, commonly
smooth, in some species covered with spines. The cephalis is usually small,
with rudimentary collar septum, at other times large, with distinct
cortinar septum. Correspondingly, the genus may be divided into different
groups, which here are enumerated as subgenera.
Subgenus 1. _Conarachnium_, Haeckel, 1881, Prodromus, p. 430. (=
_Ceratocyrtis_, Bütschli), 1882, _loc. cit._, p. 536.
_Definition._--Cephalis relatively large, with distinct collar septum and
numerous pores. Thorax smooth.
1. _Sethoconus trochus_, Haeckel.
_Eucyrtidium trochus_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 293, Taf. vii, fig. 17.
_Conarachnium trochus_, Haeckel, 1881, Prodromus, p. 430.
Cephalis ovate, relatively large, with a pyramidal horn of the same length,
and three pairs of large opposite pores, on each side of a vertical septum.
Thorax wide, conical, about as long as broad, with nearly straight
outlines; its pores regular, circular, hexagonally framed, of the same size
as the cephalic pores.
_Dimensions._--Cephalis 0.03 long, 0.02 broad; thorax 0.06 long, 0.06
broad.
_Habitat._--Tropical Pacific, Stations 200 to 281, surface.
2. _Sethoconus cucullaris_, Haeckel.
_Cornutella cucullaris_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 68, Taf. ii. fig. 7.
_Ceratocyrtis cucullaris_, Bütschli, 1882, Zeitschr. f. wiss Zool., Bd.
xxvi. p. 536, Taf. xxxiii. fig. 36, _a._, _b._
Cephalis subspherical, thorny, relatively large, with a conical horn of the
same length, and small circular pores. Thorax wide, conical, enveloping the
lower hidden half of the cephalis, about as {1291}long as broad, with
slightly convex outlines; its pores subregular, circular, half as broad as
the cephalis.
_Dimensions._--Cephalis 0.03 long, 0.02 broad; thorax 0.15 long, 0.14
broad.
_Habitat._--Fossil in Barbados.
3. _Sethoconus pileus_, n. sp.
Cephalis subspherical, free, with distinct collar stricture, a conical
oblique horn of the same length, and small, irregular, roundish pores.
Thorax flatly conical, about half as long as broad, with straight outlines;
its pores subregular, hexagonal, half as broad as the cephalis, with very
thin bars.
_Dimensions._--Cephalis 0.02 long, 0.02 broad; thorax 0.08 long, 0.16
broad.
_Habitat._--Central Pacific, Stations 262 to 274, surface.
4. _Sethoconus ampliatus_, Haeckel.
_Cornutella ampliata_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 68, Taf. ii. fig. 5.
_Ceratocyrtis ampliata_, Bütschli, 1882, Zeitschr. f. wiss. Zool., Bd.
xxxvi. p. 536.
Cephalis, hemispherical, thorny, with a conical horn of twice the length;
it is separated from the thorax by a complete internal collar septum, but
without external collar stricture. Thorax flatly conical, about half as
long as broad, with straight outlines; its pores subregular, hexagonal,
about as large as the cephalis, with thin bars.
_Dimensions._--Cephalis 0.015 long, 0.03 broad; thorax 0.08 long, 0.18
broad.
_Habitat._--Fossil in Barbados.
5. _Sethoconus mitra_, Haeckel.
_Cornutella mitra_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 68, Taf. ii. fig. 8.
_Ceratocyrtis mitra_, Bütschli, 1882, Zeitschr. f. wiss. Zool., Bd.
xxxvi. p. 536.
Cephalis ovate, with slight collar stricture (not distinct enough in
Ehrenberg's figure), with few large pores, and a conical stout horn of the
same length. Thorax campanulate, conical, twice as long as broad, with
slightly convex outlines; its pores subregular, roundish, increasing in
size towards the mouth, the largest as broad as the cephalis.
_Dimensions._--Cephalis 0.03 long, 0.02 broad; thorax 0.12 long, 0.07
broad.
_Habitat._--Tropical Atlantic, Station 347, depth 2250 fathoms; fossil in
Barbados.
6. _Sethoconus rayianus_, n. sp. (Pl. 58, fig. 6).
_Conarachnium rayianum_, Haeckel, 1881, Prodromus, p. 430.
Cephalis ovate, with obliterated collar stricture (but distinct internal
septum), with small, irregular pores, and two to four divergent horns,
which are longer than the cephalis, and two or three of which are forked.
Thorax tent-shaped, conical, two-thirds as long as broad, with slightly
{1292}concave outlines, and subregular, hexagonal pores, gradually
increasing towards the mouth, the largest half as broad as the cephalis.
This elegant species is dedicated to Dr. Ray, the discoverer of many rare
Radiolarians in the Challenger collection.
_Dimensions._--Cephalis 0.03 long, 0.02 broad; thorax 0.08 long, 0.12
broad.
_Habitat._--Central Pacific, Stations 266 to 272, surface.
7. _Sethoconus cervus_, Haeckel.
? _Eucyrtidium cervus_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 291, Taf. ix. fig. 21.
_Conarachnium cervus_, Haeckel, 1881, Prodromus, p. 430.
Cephalis subspherical, with slight collar stricture, small circular pores,
and two to four divergent horns, one or two of which are forked. Thorax
wide, conical, about as long as broad, with straight outlines and
irregular, polygonal pores, gradually increasing towards the mouth; the
largest as broad as the cephalis.
_Dimensions._--Cephalis 0.015 long, 0.02 broad; thorax 0.08 long, 0.08
broad.
_Habitat._--Indian Ocean; Maldive Islands, surface (Haeckel); Zanzibar,
depth 2200 fathoms (Pullen).
8. _Sethoconus lophophæna_, n. sp.
_Conarachnium lophophæna_, Haeckel, 1881, Prodromus, p. 430.
Cephalis subspherical, with distinct collar stricture, small circular
pores, and numerous (twelve to sixteen) radial, bristle-shaped horns of
different lengths. Thorax wide, conical, somewhat longer than broad, with
slightly convex outlines, and subregular, hexagonal pores, increasing
gradually in size towards the mouth; the largest twice as broad as the
cephalis.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.2 long, 0.16 broad.
_Habitat._--South Pacific, Station 300, depth 1375 fathoms.
9. _Sethoconus larvatus_, Haeckel.
_Lophophæna larvata_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 78, Taf. viii. fig. 10.
_Dictyocephalus larvatus_, Bütschli, 1882, Zeitschr. f. wiss. Zool., Bd.
xxxvi. p. 535.
Cephalis subspherical, large, with sharp collar stricture, and numerous
(five to ten or more) radial, conical (partly forked) horns of different
lengths. Thorax wide, conical, somewhat broader than long, with straight
outlines. Pores of both joints very irregular, roundish, of very different
sizes and form.
_Dimensions._--Cephalis 0.04 long, 0.05 broad; thorax 0.1 long, 0.12 broad.
_Habitat._--Fossil in Barbados.
{1293}10. _Sethoconus nassa_, Haeckel.
_Eucyrtidium nassa_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 72, Taf. ix. fig. 9.
Cephalis slenderly ovate, with sharp collar stricture, few scattered pores,
and a very stout, pyramidal horn of the same length, which is surrounded at
the base by three short, divergent, ascending spines (perhaps the remnants
of the three cortinar rods of _Eucecryphalus_, &c. ?). Thorax slender,
conical, with straight outlines, and small, dense, regular, circular pores
of equal size.
_Dimensions._--Cephalis 0.04 long, 0.02 broad; thorax 0.12 long, 0.08
broad.
_Habitat._--Fossil in Barbados.
11. _Sethoconus tabulatus_, Haeckel.
_Cycladophora tabulata_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 289, Taf. iv. fig. 18.
Cephalis subspherical, with slight collar stricture, and numerous small,
irregular pores, without horn, or with a small conical horn. Thorax
slenderly conical, with straight outlines, and large, regular, hexagonal
pores. Mouth truncate. (In the specimen I examined the thorax was longer
and more conically dilated; the cephalis had a distinct small horn.)
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.08 long, 0.06
broad.
_Habitat._--North Atlantic, Antilles, depth 1600 fathoms (Ehrenberg);
Station 347, depth 2250 fathoms.
Subgenus 2. _Cornutellium_ (vel _Ceratarachnium_), Haeckel, 1881,
Prodromus, p. 430.
_Definition._--Cephalis very small, rudimentary, hyaline, without distinct
collar septum, and without pores (or with scarce, rudimentary pores).
Thorax smooth.
12. _Sethoconus hexagonalis_, Haeckel.
_Cornutella trochus_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 287, Taf. ix. fig. 14.
Cephalis very small, subspherical, hyaline, without pores, with a
rudimentary horn of half the length. Thorax slenderly conical, or
bottle-shaped, twice to three times as long as broad; in the lower half
nearly cylindrical, with very thin, thread-like bars, and regular,
hexagonal pores, increasing in size towards the mouth.
_Dimensions._--Cephalis 0.005 diameter, thorax 0.12 long, 0.05 broad.
_Habitat._--Indian Ocean, Zanzibar, depth 2200 fathoms (Pullen).
13. _Sethoconus verrucosus_, Haeckel.
_Cornutella verrucosa_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 287, Taf. ix. fig. 16.
Cephalis very small, subspherical, hyaline, without pores, with a
rudimentary horn of half the {1294}length. Thorax slenderly conical, or
bottle-shaped, with little convex outlines; three to four times as long as
broad, papillate, with regular, circular pores, which are included by
rhombic frames, and increase in size towards the mouth.
_Dimensions._--Cephalis 0.004 diameter, thorax 0.12 long, 0.035 broad.
_Habitat._--Indian Ocean (Zanzibar), depth 2200 fathoms (Pullen).
14. _Sethoconus orthoceras_, n. sp. (Pl. 54, fig. 11).
_Cornutella orthoceras_, Haeckel, 1879, Atlas, _loc. cit._
Cephalis very small, conical, hyaline, without pores, with a double
internal stricture, and a very short, rudimentary horn. Thorax slenderly
conical, with undulate outlines, three to four times as long as broad, with
subregular, roundish pores, gradually increasing in size towards the mouth.
_Dimensions._--Cephalis 0.02 long, 0.01 broad; thorax 0.16 long, 0.04 to
0.08 broad.
_Habitat._--South Atlantic, Station 325, surface.
15. _Sethoconus profundus_, Haeckel.
_Cornutella profunda_, Ehrenberg, 1854, Mikrogeol., Taf. xxxv. B, Nr. B.
iv. fig. 21.
_Cornutella profunda_, Bailey, 1856, Amer. Jour., vol. xxii. pl. i. fig.
23.
_Cornutella profunda_, Haeckel, 1862 Monogr. d. Radiol., p. 284.
Cephalis very small, spherical, hyaline without pores and internal
stricture, with a very short, rudimentary horn. Thorax slenderly conical
with straight outlines, three to four times as long as broad, with
subregular, circular pores, gradually increasing in size towards the mouth.
_Dimensions._--Cephalis 0.004 to 0.008 diameter, thorax 0.08 to 0.12 long,
0.03 to 0.04 broad.
_Habitat._--Cosmopolitan; Mediterranean, Atlantic, Indian, Pacific; at
various depths.
16. _Sethoconus trichostylus_, Haeckel.
_Cornutella trichostyla_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 287, Taf. vi. fig. 2.
Cephalis very small, conical, hyaline, without pores, with a very long,
bristle-shaped, spirally twisted horn, longer than the whole shell. Thorax
slenderly conical, with straight outlines, and very small, regular,
circular pores of nearly equal size, which are separated by broader bars
and spirally ascending oblique crests (according to the figure).
_Dimensions._--Cephalis 0.004 long, 0.002 broad; thorax 0.06 long, 0.04
broad.
_Habitat._--North Pacific (California), depth 2600 fathoms.
17. _Sethoconus longisetus_, Haeckel.
_Cornutella longiseta_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 287, Taf. ix. fig. 15.
Cephalis very small, spherical, hyaline, without pores, with a very long,
bristle-shaped horn, {1295}nearly as long as the shell. Thorax slenderly
conical, rough, with straight outlines, and irregular, roundish pores,
gradually increasing in size towards the mouth.
_Dimensions._--Cephalis 0.01 diameter, thorax 0.09 long, 0.03 broad.
_Habitat._--Indian Ocean (Zanzibar), depth 2200 fathoms (Pullen).
18. _Sethoconus gracilis_, Haeckel.
_Eucyrtidium gracile_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. xi. fig. 15.
Cephalis small, subspherical, with few scarce pores, and a stout, pyramidal
horn, of the same length. Thorax slenderly conical, three to four times as
long as broad, with straight outlines, and very small and numerous circular
pores of equal size.
_Dimensions._--Cephalis 0.015 diameter, thorax 0.12 long, 0.04 broad.
_Habitat._--Fossil in Barbados.
19. _Sethoconus bimarginatus_, n. sp. (Pl. 54, fig. 12).
_Cornutella bimarginata_, Haeckel, 1879, Atlas, _loc. cit._
Cephalis very small, subspherical, hyaline, without pores, with a
rudimentary, conical horn of the same length. Thorax slenderly conical,
three times as long as broad, with undulated, little convex outlines, and
irregular, roundish, double-contoured pores, arranged in nine longitudinal
series, markedly increasing in size towards the mouth.
_Dimensions._--Cephalis 0.01 diameter, thorax 0.16 long, 0.05 broad.
_Habitat._--South Pacific, Station 300, depth 1375 fathoms.
20. _Sethoconus clathratus_, Haeckel.
_Cornutella clathrata_, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig.
39_a_, _b_, _c_.
Cephalis very small, subspherical, hyaline, without pores, with a
rudimentary horn of half the length. Thorax slenderly conical, three to
four times as long as broad, smooth, with curved axis and small, regular,
circular pores, nearly equal in size. This common species differs from all
others of the genus by the curvation of the axis of the shell, which is
more or less crescentic, or curved like a cowherd's horn; it may,
therefore, represent a peculiar genus, _Sethodrepanum_.
_Dimensions._--Cephalis 0.003 to 0.006 diameter, thorax 0.08 to 0.16 long,
0.03 to 0.05 broad.
_Habitat._--Cosmopolitan; Atlantic, Pacific, many stations; fossil in
Barbados and Sicily.
Subgenus 3. _Phlebarachnium_, Haeckel (et _Cladarachnium_, Haeckel), 1881,
Prodromus, p. 430.
_Definition._--Cephalis small, with very small pores, and internal collar
septum. Thorax spiny or thorny.
{1296}21. _Sethoconus facetus_, n. sp. (Pl. 55, fig. 1).
_Phlebarachnium facetum_, Haeckel, 1881, Prodromus, p. 430.
Cephalis small, hemispherical, with distinct collar septum, the same
network as the thorax, and numerous bristle-shaped horns of the same
length. Thorax wide, conical, about as long as broad, with slightly convex
outlines; its network extremity delicate, with very small and numerous,
regular, hexagonal pores, disposed in numerous divergent, longitudinal
series, which are convoluted somewhat spirally around the shell axis.
Surface covered with thin, scattered, bristle-shaped spines, about as long
as the cephalis.
_Dimensions._--Cephalis 0.02 diameter, thorax 0.2 long, 0.22 broad.
_Habitat._--Central Pacific, Stations 271 to 274, surface.
22. _Sethoconus anthocyrtis_, n. sp. (Pl. 62, fig. 21).
_Anthocyrtis sethoconus_, Haeckel, 1879, Atlas, _loc. cit._
Cephalis small, subspherical, with very small pores and numerous radial,
bristle-shaped spines of the same length. Thorax wide, conical, about as
long as broad, with parabolic outlines, its network very delicate, with
subregular, hexagonal meshes. Surface with scarce, bristle-shaped spines
(not represented in the figure). Mouth with a corona of numerous small,
vertical spines.
_Dimensions._--Cephalis 0.025 diameter, thorax 0.26 long, 0.24 broad.
_Habitat._--North Pacific, Station 248, surface.
23. _Sethoconus virgultus_, n. sp.
_Cladarachnium virgultum_, Haeckel, 1881, Prodromus, p. 430.
Cephalis and thorax nearly of the same form and stricture as in _Sethoconus
facetus_, but larger and wider, with the same delicate, hexagonal network
(Pl. 55, fig. 1); it differs from the latter by the wider, more convex and
campanulate form, but mainly by the armature of the surface, which is
densely covered with thin, arborescent, bristle-shaped spines, irregularly
branched, and four to eight times as large as the cephalis.
_Dimensions._--Cephalis 0.02 diameter, thorax 0.32 long, 0.4 broad.
_Habitat._--South Pacific, Station 288, surface.
24. _Sethoconus setosus_, n. sp.
_Phlebarachnium setosum_, Haeckel, 1881, Prodromus, p. 430.
Cephalis small, subspherical, with distinct collar septum, and the same
network as the thorax, with numerous bristle-shaped horns of the same
length. Thorax slenderly conical, twice as long as broad, with irregular,
polygonal pores of little different sizes, and very thin bars. Surface
covered with perpendicular, simple, bristle-shaped spines, about as long as
the cephalis.
_Dimensions._--Cephalis 0.02 diameter, thorax 0.12 long, 0.22 broad.
_Habitat._--Central Pacific, Stations 266 to 272, surface.
{1297}25. _Sethoconus venosus_, n. sp. (Pl. 55, fig. 2).
_Phlebarachnium venosum_, Haeckel, 1881, Prodromus, p. 430, et Atlas,
_loc. cit._
Cephalis subspherical, with a stout prismatic horn twice the length,
bearing three denticulate edges. The uppermost part of the thorax is
supported by three diverging, radial beams arising from the deep collar
stricture. Thorax wide, conical, nearly twice as long as broad, with
slightly convex, thorny outlines; its delicate network is composed of very
irregular, polygonal meshes of different sizes, separated by stronger bars,
and of numerous very small polygonal pores separated by very thin bars
inside the former. The central capsule of the figured specimen exhibited in
the upper third of the thorax four large club-shaped lobes, which arose
from a very small sphere enclosed in the cephalis and containing the
nucleus.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.4 long, 0.3 broad.
_Habitat._--Central Pacific, Station 271, surface.
Genus 573. _Periarachnium_,[190] Haeckel, 1881, Prodromus, p. 430.
_Definition._--#Sethocorida# (vel Dicyrtida eradiata aperta) with conical
or campanulate, gradually dilated thorax, and widely open mouth. Primary
lattice-shell enveloped by an external arachnoidal mantle. Cephalis with
one or more horns.
The genus _Periarachnium_ has been derived from those forms of the
preceding _Sethoconus_, in which the conical thorax is covered with simple
spines (_Phlebarachnium_) or branched spines (_Cladarachnium_). By
communication of the branches of these spines a second outer shell is
formed, which, like an arachnoidal mantle, envelops the inner primary
shell.
1. _Periarachnium periplectum_, n. sp. (Pl. 55, fig. 11).
Cephalis hemispherical, separated from the thorax by a sharp collar
stricture, from which arise three internal, diverging beams supporting its
upper third. Thorax campanulate, conical, about as long as broad, with
slightly convex outlines. The delicate lattice-work of the entire shell is
double; the inner composed of subregular, hexagonal meshes; the outer of
larger, irregular, polygonal meshes. The bars of the inner are much thicker
than the thin threads of the outer. Both shells are connected by numerous
bristle-shaped beams. The central capsule of the figured specimen exhibited
in the upper part of the thorax three club-shaped lobes, which arose from a
sphere enclosed in the cephalis and containing the nucleus.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.15 long, 0.12
broad.
_Habitat._--Central Pacific, Station 271, surface.
{1298}Genus 574. _Sethocephalus_,[191] Haeckel, 1881, Prodromus, p. 430.
_Definition._--#Sethocorida# (vel Dicyrtida eradiata aperta) with
discoidal, flatly expanded thorax. Cephalis large, without horn.
The genus _Sethocephalus_ (formerly proposed under the name
_Platycryphalus_) contains some few and rare Sethocorida, distinguished by
the very large cephalis, the collar opening of which is wide open, not
closed by cortinar beams, and surrounded by a very flat, nearly discoidal
thorax, like the brim of a hat. It is possible that this peculiar genus has
been derived from a Tricyrtid (_Theocalyptra_?) by loss of the original
cephalis, and that the apparent large cephalis is the original thorax.
1. _Sethocephalus eucecryphalus_, n. sp. (Pl. 56, fig. 13).
Cephalis very large, campanulate-conical, with irregular, polygonal pores
and thin bars. Thorax short, scarcely broader than the cephalis, beyond the
sharp collar stricture expanded like the brim of a hat, with few rows of
irregular, polygonal pores. (In the specimen figured the thorax was only
half as broad as in another specimen found afterwards.)
_Dimensions._--Cephalis 0.12 long, 0.09 broad; thorax 0.02 long, 0.12
broad.
_Habitat._--South Pacific, Station 285, surface.
2. _Sethocephalus platycryphalus_, n. sp.
_Platycryphalus sethodiscus_, Haeckel, 1881, Prodromus, p. 430.
Cephalis large, hemispherical, with irregular square pores and thin bars.
Thorax flatly conical, three to four times as broad as the cephalis, beyond
the collar stricture expanded nearly discoidally, with a delicate network
of small, subregular, hexagonal pores. (Similar in general form to
_Sethophormis aurelia_, Pl. 55, fig. 3, but without any trace of collar
beams or radial ribs.)
_Dimensions._--Cephalis 0.04 long, 0.08 broad; thorax 0.04 long, 0.3 broad.
_Habitat._--South Pacific, Station 289, surface.
Genus 575. _Sethocyrtis_,[192] n. gen.
_Definition._--#Sethocorida# (vel Dicyrtida eradiata aperta) with ovate or
subcylindrical thorax, the mouth of which is constricted, simple, without
prominent hyaline peristome. Cephalis with an apical horn.
{1299}The genus _Sethocyrtis_ and the three following nearly allied genera
differ from the three preceding genera of Sethocorida in the form of the
thorax, which is not gradually dilated, conical, but cylindrical or ovate,
with more or less constricted mouth. _Sethocyrtis_ may be derived from
_Anthocyrtis_ by loss of the terminal feet. Its mouth is quite simple,
without tubular or annular peristome.
1. _Sethocyrtis oxycephalis_, n. sp. (Pl. 62, fig. 9).
Shell rough, subconical, with slight collar stricture. Length of the two
joints = 4 : 9, breadth = 3 : 8. Cephalis ovate, with a pyramidal horn of
half the length. Thorax campanulate, with regular, circular pores, twice as
broad as those of the cephalis. Mouth constricted, scarcely half as broad
as the thorax.
_Dimensions._--Cephalis 0.04 long, 0.03 broad; thorax 0.09 long, 0.08
broad.
_Habitat._--Central Pacific, Stations 263 to 274, depth 2350 to 3000
fathoms.
2. _Sethocyrtis cancrina_, Haeckel.
_Eucyrtidium cancrinum_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. x. fig. 4.
Shell smooth, bottle-shaped, with obliterated collar stricture. Length of
the two joints = 4 : 9, breadth = 2 : 7. Cephalis subcylindrical, with a
stout conical horn of the same length, and sometimes a smaller accessory
horn at its base. Thorax ovate, truncate, with regular, circular,
quincuncial pores, twice as broad as those of the cephalis. Mouth little
constricted, flat, nearly as broad as the thorax.
_Dimensions._--Cephalis 0.04 long, 0.02 broad; thorax 0.09 long, 0.07
broad.
_Habitat._--Fossil in Barbados.
3. _Sethocyrtis diomedis_, n. sp.
Shell thorny, pear-shaped, with slight collar stricture. Length of the two
joints = 3 : 16, breadth = 4 : 20. Cephalis hemispherical, with a conical
horn of twice the length. Thorax inflate, ovate, truncate at both poles,
with regular, circular pores, twice as broad as those of the thorax. Mouth
constricted, flat, half as broad as the thorax.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.12 to 0.16 long,
0.16 to 0.2 broad.
_Habitat._--Central Pacific, Stations 265 to 268, depth 2700 to 2900
fathoms; also fossil in Barbados.
4. _Sethocyrtis menelai_, n. sp.
Shell spiny, pear-shaped, with sharp collar stricture. Length of the two
joints = 3 : 15, breadth = 4 : 18. Cephalis subspherical, with a large,
cylindro-conical horn, about as long as the whole shell. {1300}Thorax
inflate, subspherical, truncate, with large, irregular, roundish pores,
four to six times as large as those of the cephalis. Mouth constricted,
flat, one-third as broad as the thorax.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.15 long, 0.18
broad.
_Habitat._--Fossil in Barbados.
5. _Sethocyrtis subacuta_, Haeckel.
_Eucyrtidium subacutum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 293, Taf. vii. fig. 18.
Shell smooth, pear-shaped, with sharp collar stricture. Length of the two
joints = 1 : 4, breadth = 1 : 3. Cephalis subspherical, with small,
irregular pores and a rudimentary horn of half the length. Thorax ovate,
with large, subregular, hexagonal pores and thin bars between them. Mouth
constricted, flat, half as broad as the thorax, without prominent
peristome.
_Dimensions._--Cephalis 0.02 long, 0.02 broad; thorax 0.08 long, 0.06
broad.
_Habitat._--Philippine Sea, depth 3300 fathoms (Ehrenberg).
6. _Sethocyrtis pleuracantha_, Haeckel.
_Eucyrtidium pleuracanthum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d.
Wiss. Berlin, p. 293, Taf. vii. fig. 21.
Shell smooth, bottle-shaped, with distinct collar stricture. Length of the
two joints = 2 : 4, breadth = 1 : 3. Cephalis slenderly ovate, with an
excentric pyramidal horn of the same length. Thorax inflate, ovate, with
irregular, roundish pores and thin bars between them. Mouth constricted,
flat, half as broad as the thorax, without prominent peristome.
_Dimensions._--Cephalis 0.04 long, 0.02 broad; thorax 0.08 long, 0.06
broad.
_Habitat._--Tropical Pacific, Stations 200, 225, 266, 274, &c., at various
depths.
7. _Sethocyrtis agamemnonis_, n. sp. (Pl. 62, figs. 11, _a_, _b_).
Shell pear-shaped, rough, with sharp collar stricture. Length of the two
joints = 2 : 10, breadth = 3 : 8. Cephalis subspherical, with very small
pores and a small, pyramidal horn of half the length. Thorax inflate,
ovate; in the uppermost part (beyond the collar stricture) with a ring of
six to nine very large roundish pores, which are twice to four times as
broad as the other irregular, roundish pores. (The shell is seen in fig. 11
from the apical pole, in fig. 11_a_ with the cephalis, in fig. 11_b_
without it, exhibiting the four central collar pores of the cortinar
septum.) Mouth truncate, without prominent peristome.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.1 long, 0.08 broad.
_Habitat._--North Pacific, Station 244, depth 2900 fathoms.
{1301}8. _Sethocyrtis cassis_, Haeckel.
_Cornutella cassis_, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 38.
_Cyrtocalpis cassis_, Haeckel, 1862, Monogr. d. Radiol., p. 287.
Shell pear-shaped, smooth, with obliterated collar stricture. Length of the
two joints = 4 : 13, breadth = 3 : 12. Cephalis ovate, with a conical horn
of half the length. Thorax inflate, ovate, with subregular, circular,
quincuncial pores, twice to three times as broad as the bars. Mouth
constricted, truncate, two-thirds as broad as the thorax, without prominent
peristome.
_Dimensions._--Cephalis 0.04 long, 0.03 broad; thorax 0.13 long, 0.12
broad.
_Habitat._--Fossil in Tertiary rocks of Sicily (Caltanisetta).
Genus 576. _Sethocorys_,[193] Haeckel, 1881, Prodromus, p. 430.
_Definition._--#Sethocorida# (vel Dicyrtida eradiata aperta) with ovate or
sub-cylindrical thorax, the mouth of which is constricted and prolonged
into a ring-like peristome. Cephalis with an apical horn.
The genus _Sethocorys_ differs from the preceding _Sethocyrtis_, its
ancestral form, in the form of the constricted mouth, which is prolonged
into a prominent, hyaline, tubular, or annular peristome.
1. _Sethocorys achillis_, n. sp. (Pl. 62, fig. 8).
Shell rough, pear-shaped, with distinct collar stricture. Length of the two
joints = 4 : 8, breadth = 3 : 8. Cephalis ovate, with a stout pyramidal
horn of half the length. Thorax nearly spherical, with regular, circular,
quincuncial pores of the same breadth as the cephalic pores. Mouth
constricted, half as broad as the thorax, with a broad, smooth, striated
peristome.
_Dimensions._--Cephalis 0.04 long, 0.03 broad; thorax 0.08 long, 0.08
broad.
_Habitat._--Cosmopolitan; Mediterranean (Corfu), Atlantic, Indian, Pacific;
many stations, at various depths.
2. _Sethocorys patrocli_, n. sp.
Shell thorny, pear-shaped, with slight collar stricture. Length of the two
joints = 4 : 12, breadth = 3 : 10. Cephalis ovate, with a pyramidal horn of
twice the length. Thorax ovate, truncate at both poles, with regular,
circular pores, twice as broad as the cephalic pores. Mouth constricted,
half as broad as the thorax, with a broad, smooth, prominent peristome.
_Dimensions._--Cephalis 0.04 long, 0.03 broad; thorax 0.12 long, 0.1 broad.
_Habitat._--Central Pacific, Stations 263 to 274, depth 2350 to 3000
fathoms.
{1302}3. _Sethocorys armadillo_, Haeckel.
_Eucyrtidium armadillo_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf ix. fig. 10.
Shell slenderly ovate, smooth, with deep collar stricture. Length of the
two joints = 3 : 10, breadth = 4 : 6. Cephalis ovate, at the apex thorny,
with a conical horn of the same length. Thorax smooth, ovate, truncate,
with small, regular, circular pores, disposed in from twelve to fifteen
transverse rows of the same breadth as the cephalic pores. Mouth
constricted, half as broad as the thorax, with a broad, hyaline, prominent
peristome.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.1 long, 0.06 broad.
_Habitat._--Fossil in Barbados.
4. _Sethocorys odysseus_, n. sp. (Pl. 62, fig. 10).
Shell ovate, smooth, with obliterated collar stricture. Length of the two
joints = 2 : 9, breadth = 4 : 8. Cephalis hemispherical, with a slender,
conical horn of the same length. Thorax nearly spherical, with regular,
circular pores, of the same breadth as the cephalic pores, quincuncially
disposed. Mouth constricted, only one-third as broad as the thorax, with a
broad, hyaline, prominent peristome.
_Dimensions._--Cephalis 0.02 long, 0.04 broad; thorax 0.09 long, 0.08
broad.
_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.
5. _Sethocorys amphora_, Haeckel.
_Lophophæna amphora_, Stöhr, 1880, Palæontogr., vol. xxvi. p. 99, Taf.
iii. fig. 11.
Shell ovate, mouth with distinct collar stricture. Length of the two joints
= 1 : 5, breadth = 2 : 4. Cephalis hemispherical, with a short conical horn
of half the length. Thorax ovate, truncate, with small, regular, circular,
quincuncial pores. Mouth constricted, half as broad as the thorax, with a
narrow, prominent, hyaline peristome.
_Dimensions._--Cephalis 0.015 long, 0.03 broad; thorax 0.07 long, 0.06
broad.
_Habitat._--Fossil in Tertiary rocks of Sicily; Grotte (Stöhr).
6. _Sethocorys ajacis_, n. sp.
Shell slenderly ovate, smooth, without external collar stricture, but with
an internal septum. Length of the two joints = 1 : 3, breadth = 1 : 2.
Cephalis conical, with a large pyramidal horn of twice the length, and
sometimes with a smaller accessory horn at its base; its pores scarce,
irregular. Thorax ovate, truncate, hyaline, in the greater part without
pores, in the smaller part {1303}with from two to four transverse rows of
small, circular pores only. Mouth constricted, with a large cylindrical,
tubular, hyaline peristome, half as long as the shell.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.09 long, 0.07
broad.
_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.
Genus 577. _Lophophæna_,[194] Ehrenberg, 1847, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 54.
_Definition._--#Sethocorida# (vel Dicyrtida eradiata aperta) with ovate or
subcylindrical thorax, the mouth of which is either truncate or
constricted. Cephalis armed with several large horns.
The genus _Lophophæna_ differs from the nearly allied _Sethocorys_ and
_Dictyocephalus_ only in the armature of the large cephalis, which bears a
group of large horns, often arranged in a corona of radial spines.
Sometimes these spines are connected by anastomosing branches (like
_Arachnocorys_).
Subgenus 1. _Lophophænula_, Haeckel.
_Definition._--Horns of the cephalis simple, free, radial spines, neither
branched nor connected.
1. _Lophophæna galea_, Ehrenberg.
_Lophophæna galea orci_, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad.
d. Wiss. Berlin p. 245.
_Lophophæna apiculata_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 78, Taf. viii. fig. 11.
? _Cornutella spiniceps_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 68, Taf. ii. fig. 6.
Shell with slight collar stricture. Length of the two joints = 5 : 4,
breadth = 5 : 6. Cephalis subglobular, with numerous bristle-shaped, radial
spines, about as long as its radius. Thorax about the same size, truncate,
conical, smooth, with wide open mouth. Pores in both joints of equal size,
small, regular, circular.
_Dimensions._--Cephalis 0.05 long, 0.05 broad; thorax 0.04 long, 0.06
broad.
_Habitat._--Tropical Atlantic, Station 348, depth 2450 fathoms; also fossil
in Barbados.
3. _Lophophæna radians_, Ehrenberg.
_Lophophæna radians_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 78, Taf. viii. fig. 9.
? _Lophophæna lynx_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 78, Taf. viii. fig. 13.
Shell with slight collar stricture. Length of the two joints = 4 : 6,
breadth = 4 : 5. Cephalis subglobular, with numerous, stout, conical,
radial spines, about as long as its diameter. Thorax {1304}of about the
same size, subcylindrical, smooth, truncate, with wide open mouth. Pores in
both joints of equal size, small, regular, circular.
_Dimensions._--Cephalis 0.04 long, 0.04 broad; thorax 0.06 long, 0.05
broad.
_Habitat._--Cosmopolitan; Atlantic, Indian, Pacific; also fossil in
Barbados.
3. _Lophophæna liothorax_, n. sp.
Shell with distinct collar stricture. Length of the two joints = 4 : 10,
breadth = 4 : 8. Cephalis subglobular, with large, circular,
hexagonally-framed pores, and with numerous stout, conical, radial spines,
about as long as its diameter. Thorax twice as long, ovate, smooth,
truncate, with little constricted mouth, and with irregular, roundish
pores, of very different sizes.
_Dimensions._--Cephalis 0.04 long, 0.04 broad; thorax 0.1 long, 0.08 broad.
_Habitat._--Central Pacific, Stations 270 to 274, depth 2350 to 2925
fathoms.
4. _Lophophæna echinocephala_, n. sp.
Shell with deep collar stricture. Length of the two joints = 4 : 8, breadth
= 4 : 9. Cephalis subglobular, of the same shape as in the preceding
species. Thorax thorny, inflate, nearly spherical, with a constricted mouth
of half the breadth, and with irregular, roundish, double-contoured pores.
_Dimensions._--Cephalis 0.04 long, 0.04 broad; thorax 0.08 long, 0.09
broad.
_Habitat._--North Pacific, Station 253, depth 3125 fathoms.
Subgenus 2. _Lophophænoma_, Haeckel.
_Definition._--Horns of the cephalis connected by anastomosing branches.
5. _Lophophæna circumtexta_, Haeckel.
_Lophophæna radians_, var., Ehrenberg, 1875, Abhandl. d. k. Akad. d.
Wiss. Berlin, p. 78, Taf. viii. figs. 7, 8.
Shell with slight collar stricture. Length of the two joints = 4 : 5,
breadth = 4 : 5. Cephalis subglobular, with numerous conical, radial
spines, about as long as its diameter, and at equal distances from the
surface, connected by anastomosing branches. Thorax nearly cylindrical,
smooth, little dilated towards the truncate, wide open mouth. Pores
subregular, circular.
_Dimensions._--Cephalis 0.04 long, 0.04 broad; thorax 0.05 long, 0.05
broad.
_Habitat._--Central Pacific, Stations 265 to 268, depth 2700 to 2900
fathoms; also fossil in Barbados.
{1305}Genus 578. _Dictyocephalus_,[195] Ehrenberg, 1860, Monatsber. d. k.
preuss. Akad. d. Wiss. Berlin, p. 830.
_Definition._--#Sethocorida# (vel Dicyrtida eradiata aperta) with ovate or
subcylindrical thorax, the mouth of which is more or less constricted,
either truncate or with a ring-like peristome. Cephalis rounded, without
horn.
The genus _Dictyocephalus_ has originated probably from _Sethocorys_ by
reduction and loss of the apical horn. The mouth is more or less
constricted, either simple, truncate (_Dictyocryphalus_), or provided with
a prominent, broad, hyaline, annular peristome (_Dictyoprora_).
Subgenus 1. _Dictyoprora_, Haeckel, 1881, Prodromus, p. 430.
_Definition._--Mouth of the thorax constricted, with a prominent, ring-like
or tubular, hyaline peristome.
1. _Dictyocephalus amphora_, n. sp. (Pl. 62, fig. 4).
Shell smooth, thick-walled, subovate, with slight collar stricture. Length
of the two joints = 5 : 9, breadth = 6 : 8. Cephalis large, obtusely
conical, with numerous oblique pore-canals. Thorax inflate, with six to
eight transverse rows of roundish pores, increasing in size towards the
base. Mouth constricted, one-third as broad as the thorax, with an internal
diaphragm and a narrow hyaline peristome.
_Dimensions._--Cephalis 0.05 long, 0.06 broad; thorax 0.09 long, 0.08
broad.
_Habitat._--Central Pacific, Stations 265 to 272, depth 2425 to 2925
fathoms.
2. _Dictyocephalus urceolus_, n. sp.
? _Eucyrtidium Mongolfieri_, Bury, 1862, Polycystins of Barbados, pl. v.
fig. 2.
Shell smooth, thick-walled, urceolate, with obliterated collar stricture.
Length of the two joints = 5 : 12, breadth = 4 : 10. Cephalis campanulate,
with numerous oblique pore-canals. Thorax inflate, with five or six
transverse rows of roundish pores of equal size. Mouth constricted, nearly
half as broad as the thorax, with a broad hyaline peristome.
_Dimensions._--Cephalis 0.05 long, 0.04 broad; thorax 0.12 long, 0.1 broad.
_Habitat._--Central Pacific, Station 268, depth 2900 fathoms; also fossil
in Barbados.
{1306}3. _Dictyocephalus excellens_, Haeckel.
_Eucyrtidium excellens_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. x. fig. 2.
Shell annulate, thick-walled, urceolate, with slight collar stricture.
Length of the two joints = 5 : 10, breadth = 4 : 7. Cephalis large,
ovate-conical, with numerous oblique pore-canals. Thorax ovate, with ten to
twelve transverse rows of regular, roundish pores, which are separated by
prominent annular ribs. Mouth constricted, about half as broad as the
thorax, with a broad hyaline peristome.
_Dimensions._--Cephalis 0.05 long, 0.04 broad; thorax 0.1 long, 0.07 broad.
_Habitat._--Fossil in Barbados.
4. _Dictyocephalus ocellatus_, Haeckel.
_Dictyocephalus ocellatus_, Haeckel, 1862, Monogr. d. Radiol., p. 297.
? _Eucyrtidium ocellatum_, Ehrenberg, 1861, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 299.
Shell smooth, thick-walled, with deep collar stricture. Length of the two
joints = 3 : 9, breadth = 4 : 7. Cephalis subspherical, with numerous
oblique pore-canals. Thorax inflate, campanulate, hyaline, only with three
or four remote transverse rows of circular, double-contoured pores of equal
size. Mouth constricted, one-third as broad as the thorax, with a narrow
hyaline annular peristome.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.09 long, 0.07
broad.
_Habitat._--North Atlantic, Greenland; Færöe Channel (Gulf Stream), John
Murray.
5. _Dictyocephalus crassiceps_, Haeckel.
_Eucyrtidium crassiceps_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. xi. fig. 4.
Shell smooth, thick-walled, with sharp collar stricture. Length of the two
joints = 4 : 6, breadth = 3 : 4. Cephalis ovate, in the upper part with
scattered pores, in the lower part with one transverse row of pores. Thorax
hyaline, subcylindrical, only with four or five remote transverse rows of
small, circular pores. Mouth constricted, half as broad as the thorax, with
a short hyaline peristome.
_Dimensions._--Cephalis 0.04 long, 0.03 broad; thorax 0.06 long, 0.04
broad.
_Habitat._--Fossil in Barbados.
6. _Dictyocephalus australis_, n. sp. (Pl. 62, fig. 1).
Shell smooth, thick-walled, with slight collar stricture. Length of the two
joints = 2 : 9, breadth = 3 : 6. Cephalis hemispherical, with few small
pores. Thorax subcylindrical, with large, {1307}roundish, double-contoured
pores, irregularly disposed. Mouth constricted, two-thirds as broad as the
thorax, with a broad, hyaline peristome.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.09 long, 0.06
broad.
_Habitat._--East coast of Australia, Station 164, surface.
7. _Dictyocephalus mediterraneus_, n. sp. (Pl. 62, fig. 2).
Shell rough, thin-walled, with slight collar stricture. Length of the two
joints = 3 : 10, breadth = 4 : 8. Cephalis hemispherical, with small,
circular pores. Thorax ovate, truncate, with much larger circular pores of
different sizes and thin bars between them. Mouth little constricted,
two-thirds as broad as the thorax, with a narrow, hyaline peristome.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.1 long, 0.08 broad.
_Habitat._--Mediterranean, Smyrna (Haeckel), surface.
8. _Dictyocephalus papillosus_, Haeckel.
_Eucyrtidium papillosum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 293, Taf. vii. fig. 10.
Shell thin-walled, papillate, with obliterated collar stricture. Length of
the two joints = 2 : 7, breadth = 3 : 5. Cephalis hemispherical, with
small, circular pores. Thorax slenderly ovate, with larger, subregular,
circular pores, separated by oblique series of conical papillæ. Mouth with
a broad, hyaline peristome (the "third articulus" of Ehrenberg), separated
by a stricture from the little broader thorax.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.07 long, 0.05
broad.
_Habitat._--Western Tropical Pacific (Philippine Sea), depth 3300 fathoms.
9. _Dictyocephalus tabulatus_, n. sp.
Shell thin-walled, papillate, with obliterated collar stricture. Length of
the two joints = 2 : 10, breadth = 3 : 7. Cephalis hemispherical, with
small, circular pores. Thorax slenderly ovate, truncate, with large,
subregular, circular, hexagonally-framed pores. Mouth little constricted,
nearly as broad as the thorax, with a broad, hyaline peristome.
_Dimensions._--Cephalis 0.02 long, 0.03 broad, thorax 0.1 long, 0.07 broad.
_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.
10. _Dictyocephalus reticulum_, Haeckel.
_Dictyocephalus reticulum_, Haeckel, 1862, Monogr. d. Radiol., p. 297.
_Eucyrtidium reticulum_, Ehrenberg, 1861, Monatsber. d. k. preuss. Akad.
d. Wiss. Berlin, p. 300.
Shell thin-walled, smooth, with deep collar stricture. Length of the two
joints = 2 : 8, breadth = 3 : 5. Cephalis subspherical, with small,
circular pores. Thorax campanulate, with {1308}transverse rows of
alternating square pores. Mouth little constricted, nearly as long as the
thorax, with a narrow, prominent peristome.
_Dimensions._--Cephalis 0.02 long, 0.03 broad; thorax 0.08 long, 0.05
broad.
_Habitat._--Arctic Ocean, Greenland (Schaffner); Iceland (Krabbe).
11. _Dictyocephalus ampulla_, n. sp.
Shell thin-walled, smooth, with slight collar stricture. Length of the two
joints = 1 : 4, breadth = 1 : 3. Cephalis subspherical, without pores,
hyaline. Thorax inflate, subspherical, with scarce and small,
widely-scattered, circular pores. Mouth constricted, only one-third as
broad as the thorax, with a narrow, prominent peristome.
_Dimensions._--Cephalis 0.02 long, 0.02 broad; thorax 0.08 long, 0.07
broad.
_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.
Subgenus 2. _Dictyocryphalus_, Haeckel, 1881, Prodromus, p. 430.
_Definition._--Mouth of the thorax flat or truncate, without prominent
ring-like peristome.
12. _Dictyocephalus obtusus_, Ehrenberg.
_Dictyocephalus obtusus_, Ehrenberg, 1860, Monatsber. d. k. preuss. Akad.
d. Wiss. Berlin, p. 830.
_Lophophæna obtusa_, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 40.
_Cornutella obtusa_, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d.
Wiss. Berlin, p. 877.
_Dictyocephalus obtusus_, Haeckel, 1862, Monogr. d. Radiol., p. 296.
Shell smooth, thick-walled, with distinct collar stricture. Length of the
two joints = 5 : 6, breadth = 4 : 5. Cephalis ovate, little smaller than
the subcylindrical thorax. Pores subregular, circular, of little different
sizes. Mouth truncate, without ring-like peristome.
_Dimensions._--Cephalis 0.05 long, 0.04 broad; thorax 0.06 long, 0.05
broad.
_Habitat._--Fossil in Tertiary rocks of Sicily (Caltanisetta), Grotte, &c.
13. _Dictyocephalus globiceps_, n. sp. (Pl. 62, fig. 7).
Shell rough, thin-walled, with distinct collar stricture. Length of the two
joints = 6 : 8, breadth = 6 : 7. Cephalis subspherical, large, with
circular, double-contoured pores. Thorax cylindrical, with irregular,
roundish pores, the size of which, like the thickness of the wall,
decreases gradually towards the truncate mouth, which has no ring-like
peristome.
_Dimensions._--Cephalis 0.06 long, 0.06 broad; thorax 0.08 long, 0.07
broad.
_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.
{1309}14. _Dictyocephalus cavea_, n. sp.
Shell rough, thin-walled, with slight collar stricture. Length of the two
joints = 3 : 10, breadth = 5 : 7. Cephalis hemispherical, thorny, with
numerous regular, circular pores. Thorax subcylindrical, with very large,
circular, hexagonally-framed pores (in nine longitudinal alternating rows),
three to five times as broad as the cephalic pores. Mouth truncate, wide
open, without ring-like peristome.
_Dimensions._--Cephalis 0.06 long, 0.1 broad; thorax 0.2 long, 0.14 broad.
_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.
15. _Dictyocephalus capito_, Ehrenberg.
_Dictyocephalus capito_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 289, Taf. vii. fig. 24.
Shell smooth, thin-walled, with sharp collar stricture. Length of the two
joints = 7 : 9, breadth = 6 : 8. Cephalis ovate, with numerous irregular,
roundish, densely-crowded pores. Thorax ovate, with very few
widely-scattered, irregular, roundish pores (broken off in Ehrenberg's
figure). Mouth truncate, little constricted, without ring-like peristome.
_Dimensions._--Cephalis 0.07 long, 0.06 broad; thorax 0.09 long, 0.08
broad.
_Habitat._--Western Tropical Pacific (Philippine Sea) Station 206, depth
2100 fathoms.
16. _Dictyocephalus hispidus_, Ehrenberg.
_Dictyocephalus hispidus_, Ehrenberg, Monatsber. d. k. preuss. Akad. d.
Wiss. Berlin; Abhandl. d. k. Akad. d. Wiss. Berlin, 1872, p. 289, Taf. v.
fig. 18.
Shell rough, thin-walled, with deep collar stricture. Length of the two
joints = 3 : 4, breadth = 3 : 5. Cephalis subspherical, spiny, with the
same irregular, roundish pores as the funnel-shaped or nearly ovate thorax.
Mouth truncate, little narrower than the thorax, without ring-like
peristome.
_Dimensions._--Cephalis 0.03 long, 0.03 broad; thorax 0.04 long, 0.05
broad.
_Habitat._--Tropical Atlantic, Mexican Gulf (Ehrenberg); Station 338, depth
1990 fathoms.
Subfamily 2. SETHOCAPSIDA, Haeckel, 1881, Prodromus, p. 433.
_Definition._--#Sethocyrtida# with the basal mouth of the shell fenestrated
(vel Dicyrtida eradiata clausa).
{1310}Genus 579. _Sethocapsa_,[196] Haeckel, 1881, Prodromus, p. 433 (sensu
emendato).
_Definition._--#Sethocapsida# (vel Dicyrtida eradiata clausa) with a free
cephalis bearing an apical horn.
The genus _Sethocapsa_ and the two following genera represent together the
small subfamily of Sethocapsida, or those Dicyrtida in which the mouth of
the thorax is closed, and no radial apophyses are present. _Sethocapsa_ may
be derived either from _Lithopera_ by loss of the three radial rods, or
from _Sethocyrtis_ by closure of the mouth.
1. _Sethocapsa pyriformis_, n. sp. (Pl. 57, fig. 2).
Shell rough, pear-shaped, with slight collar stricture. Length of the two
joints = 3 : 10, breadth = 3 : 8. Cephalis subspherical, with numerous
small pores, and a short pyramidal or conical horn of half the length.
Thorax ovate, with subregular, circular, quincuncial pores.
_Dimensions._--Cephalis 0.03 diameter, thorax 0.1 long, 0.08 broad.
_Habitat._--Central Pacific, Stations 263 to 274, depth 2350 to 3000
fathoms.
2. _Sethocapsa lagena_, Haeckel.
_Lithopera lagena_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 78, Taf. iii. fig. 4.
Shell smooth, pear-shaped, with sharp collar stricture. Length of the two
joints = 3 : 8, breadth = 3 : 6. Cephalis pear-shaped, with few scarce
pores, and a small conical horn of half the length. Thorax pear-shaped,
with irregular, roundish pores. This species differs from the similar
_Lithopera lagena_ almost only in the complete absence of the three
internal radial collar beams inside the thorax, and may be derived from it
by their retrograde metamorphosis.
_Dimensions._--Cephalis 0.03 diameter, thorax 0.08 long, 0.06 broad.
_Habitat._--Fossil in Barbados.
3. _Sethocapsa macroceros_, n. sp.
Shell smooth, pear-shaped, with slight collar stricture. Length of the two
joints = 2 : 11, breadth = 2 : 9. Cephalis subspherical, with small
circular pores, and a very large, straight, pyramidal horn, of about the
same length as the shell. Thorax ovate, with large, irregular, roundish
pores, which are surrounded by polygonal frames.
_Dimensions._--Cephalis 0.02 diameter, thorax 0.11 long, 0.09 broad.
_Habitat._--Central Pacific, Station 270, depth 2925 fathoms.
{1311}4. _Sethocapsa nidus_, Haeckel.
_Lithopera nidus pendulus_, Ehrenberg, 1875, Abhandl. d. k. Akad. d.
Wiss. Berlin, p. 78, Taf. iii. fig. 7.
Shell smooth, pear-shaped, with distinct collar stricture. Length of the
two joints = 3 : 6, breadth = 3 : 5. Cephalis subspherical, with a large,
straight, pyramidal horn of twice the length, and scarce small pores.
Thorax ovate, also with very small and scarce pores.
_Dimensions._--Cephalis 0.03 diameter, thorax 0.06 long, 0.05 broad.
_Habitat._--Fossil in Barbados.
5. _Sethocapsa bulla_, n. sp.
Shell spiny, with slight collar stricture. Length of the two joints =
3 : 12, breadth = 4 : 12. Cephalis hemispherical, with small, scarce pores,
and a conical horn of the same length. Thorax nearly spherical, with large,
subregular, circular, quincuncial pores, twice as broad as the bars.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.12 long, 0.12
broad.
_Habitat._--Central Pacific, Station 268, depth 2900 fathoms; fossil in
Barbados.
6. _Sethocapsa ampulla_, n. sp.
Shell papillate, with slight collar stricture. Length of the two joints =
1 : 5, breadth = 1 : 5. Cephalis hemispherical, hyaline, without pores,
with a large pyramidal horn of twice the length. Thorax nearly spherical,
with large, irregular, roundish, lobulated pores.
_Dimensions._--Cephalis 0.03 long, 0.04 broad; thorax 0.15 long, 0.15
broad.
_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.
7. _Sethocapsa staurocephala_, Haeckel.
? _Lithopera oxystauros_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 78, Taf. iii. fig. 6.
? _Lithopera amblystauros_, Ehrenberg, 1875, Abhandl. d. k. Akad. d.
Wiss. Berlin, p. 78, Taf. iii. fig. 5.
Shell smooth, with slight collar stricture. Length of the two joints =
3 : 4, breadth = 3 : 4. Cephalis large, ovate, with a conical horn of the
same length, small scarce pores, and an internal frontal septum, composed
of two crossed beams, a vertical and a horizontal. Thorax little larger
than the cephalis, ovate, with irregular, small and scarce pores. (The two
figures of Ehrenberg are either incomplete--in _Lithopera amblystauros_,
the cephalic horn, and in _Lithopera oxystauros_, the basal part of the
thorax, being broken off--or they belong to different #Botryodea#).
_Dimensions._--Cephalis 0.03 diameter, thorax 0.04 diameter.
_Habitat._--Fossil in Barbados.
{1312}Genus 580. _Dicolocapsa_,[197] Haeckel, 1881, Prodromus, p. 433
(sensu emendato).
_Definition._--#Sethocapsida# (vel Dicyrtida eradiata clausa) with a free
cephalis, without apical horn.
The genus _Dicolocapsa_ differs from the preceding _Sethocapsa_ in the loss
of the apical horn, and therefore bears to it the same relation that
_Dictyocephalus_ does to _Sethocyrtis_.
1. _Dicolocapsa microcephala_, n. sp. (Pl. 57, fig. 1).
Shell smooth, thin-walled, with distinct collar stricture. Cephalis small,
subspherical, with small, crowded pores. Length of the two joints = 1 : 3,
breadth = 1 : 3. Thorax also nearly spherical, three times as large as the
cephalis, with small, irregularly scattered, circular pores, and much
broader bars.
_Dimensions._--Cephalis 0.03 diameter, thorax 0.09 diameter.
_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.
2. _Dicolocapsa megacephala_, n. sp.
Shell smooth, thin-walled, with sharp collar stricture. Cephalis large,
conical, obtuse. Length of the two joints = 5 : 9, breadth = 6 : 8. Thorax
ovate, truncate, with hemispherical base. Pores of both joints equal,
subregular, circular, about as broad as the bars.
_Dimensions._--Cephalis 0.05 long, 0.06 broad; thorax 0.09 long, 0.08
broad.
_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.
3. _Dicolocapsa platycephala_, n. sp.
Shell papillate, thick-walled, with slight collar stricture. Cephalis flat,
hemispherical, hyaline, without pores (or with few small pores). Length of
the two joints = 2 : 11, breadth = 4 : 9. Thorax ovate, with small,
regular, circular pores, half as broad as the bars.
_Dimensions._--Cephalis 0.02 long, 0.04 broad; thorax 0.11 long, 0.09
broad.
_Habitat._--Fossil in Barbados.
Genus 581. _Cryptocapsa_,[198] Haeckel, 1881, Prodromus, p. 433.
_Definition._--#Sethocapsida# (vel Dicyrtida eradiata clausa) with a
cephalis hidden in the thorax, without apical horn.
{1313}The genus _Cryptocapsa_ differs from the preceding _Dicolocapsa_, its
ancestral form, in the peculiar shape of the cephalis, which is nearly
perfectly enclosed in the upper part of the inflated thorax. It has,
therefore, to the latter the same relation as _Carpocanium_ bears to
_Anthocyrtis_.
1. _Cryptocapsa bacca_, n. sp.
Cephalis spherical, with small circular pores enclosed in the upper part of
the thorax, which is ovate, smooth, and exhibits regular, circular pores,
about as broad as the bars.
_Dimensions._--Cephalis 0.03 diameter, thorax 0.15 long, 0.12 broad.
_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.
2. _Cryptocapsa pila_, n. sp.
Cephalis spherical, with few small pores, enclosed in the upper part of the
thorax, which is pear-shaped, spiny, and exhibits subregular, hexagonal
pores, three times as broad as the bars. From each hexagon corner a small
thorn arises.
_Dimensions._--Cephalis 0.04 diameter, thorax 0.25 long, 0.17 broad.
_Habitat._--Central Pacific, Station 269, depth 2900 fathoms.
----