A species of about the size of _A. calva_, but with a proportionately
larger head. It is represented in our collection by a specimen
which lacks only a portion of the caudal and pectoral fins. The
_premaxillary_ is short and stout, articulates closely with the
maxillary, and bears a single row of pointed recurved teeth. These
are shorter and straighter than in _A. calva_. The _maxillary_ is
much as in the modern species, but is rounder. The cranio-facial axis
is straight and broad; the _basioccipital_ is the largest of the
bones; the _basisphenoid_ and _presphenoid_ are of the usual shape
and size, but there is a constriction at their junction which is not
marked in the modern species. The _vomer_ is long and double, and at
the extremity is armed with rows of small teeth. The two portions
diverge more perceptibly than in _A. calva_, and are stouter, though
this appearance may, to some extent, be due to flattening.
The _frontal_ is long, broad, and thick; the upper surface is
delicately sculptured in a somewhat different pattern from that seen
in the modern species. The _parietal_ is short and broad, while the
_epiotic_ is unusually narrow. The _mandible_ is long and slender;
the rami are incurved anteriorly, but apparently not to the same
extent as in _A. calva_. The articular has the shape of a long and
narrow wedge; it does not form a very close articulation with the
dentary. The dentary is long and comparatively slender, has a rounded
outline, and is occupied by an external row of large, and an internal
band of small teeth. The mandibular teeth, like those of the upper
jaw, are somewhat different from the teeth of _A. calva_; they are
shorter, stouter, and are not so much incurved or recurved. They
are very sharp, and show a constriction below the apex. The small
teeth are of the usual size and shape. The jugular plate is well
developed, and is long and narrow. The _hyoid arch_ is very much the
same as that shown in the recent species; the characteristic flat
branchiostegals are well marked; they appear to be thirteen in number.
The _scapular arch_ is long and stout. The _clavicle_ is strongly
bent, the supra-clavicle is short, and the _post-clavicle_ is long.
The pectoral fin is too indistinct for description.
The _vertebræ_ are of considerable depth in the anterior dorsal
region, and decrease steadily in size as they go backwards. The
neural spines are long and slender, and project strongly backwards.
The relation of the centra to the arches seems to be about that
seen in _A. calva_, but the neurapophyses are more slender. The
diapophyses are long and slender, in this respect differing from
the Bridger species and approaching the modern one. The dorsals are
thirty-five in number. The caudals number about forty-seven. They
have smaller centra, but longer and stronger neurapophyses than the
dorsals. The hæmal arch is long, and the hæmapophyses articulate
movably with the centra. The spines supporting the caudal fin rays
are very stout. The dorsal fin is long and soft, and has long
interneurals supporting short rays; these are fifty-three in number.
The anal fin, on the other hand, is very short, having but nine rays,
which are long and jointed, and articulate with short interhæmals.
The caudal fin appears to be of the usual form. The _femur_ is of the
general shape characteristic of _Amia_, but is not just like that of
_A. calva_. It is shorter, broader at the proximal end, while the
distal end is narrower, and has a deeper constriction just above it.
The ventral fins are placed under the middle of the dorsal region,
and have each ten rays. The scales are of the usual cycloidal shape,
and minutely striate.
_Measurements._
M.
Total length (estimated in part) ·404
Length of head ·093
Length of vertebral column ·253
Length of caudal fin (estimated) ·058
Length of mandible ·059
Length of jugular plate ·032
Length of dorsal region ·141
Length of caudal region ·112
Depth of body at origin of dorsal fin
Length of dorsal fin ·117
Length of femur ·027
From the insect beds near Florissant, Col.
PAPPICHTHYS, Cope.
U. S. Geol. Survey of the Terrs., 1872, p. 634.
Vertebræ short, dorsal with projecting diapophyses. Maxillary and
dentary bones support but one series of teeth.
Pappichthys plicatus, Cope.
Loc. cit., p. 635.
From Henry's Fork.
Pappichthys lævis, Cope.
Loc. cit., p. 366.
Represented by three vertebræ from the posterior part of the dorsal
region. The centra are subcircular and have deep articular cones,
with their bottoms above the centre, and minutely perforate for
the notochord. The centra are comparatively quite long, and have
prominent projecting rims, and are truncate beneath. The facets for
the neurapophyses are long, and are separated into two parts for the
contiguous arches. The diapophyses are short and stout.
Measurements.
M.
Length of centrum ·015
Breadth of centrum ·0315
Depth of centrum ·027
Found at Henry's Fork.
Pappichthys symphysis, Cope.
Loc. cit., p. 636.
Found at Cottonwood Creek.