Type--M. C. Z. 2, 139.
_Halosydna leioseta_ sp. nov.
Body strongly and continuously narrowed caudad. Prostomium wider than
long, deeply bilobed, the median tentacle inserted deeply in the
intervening incision. Lobes extended forward into peaks which, however,
are constricted at base so as to give appearance of more or less
distinct ceratophores, these short. Anterior eye free on each side,
the caudal one much farther mesad and overlapped by the peristomium.
Tentacles short, the median line a little longest and about equalling
the palpi; in each a slender tip above the moderate subdistal swelling
about equal in length to the remaining part of the style. Tentacular
cirri similarly formed, as is also the first neurocirrus, the latter
less clavate below the slender tip. Other neurocirri much shorter,
shortly subfusiform with filiform tip short; characteristically
inserted almost precisely at middle of length of the neuropodium.
Notopodia reduced to small lobes at base of neuropodia above, these
lobes smooth, bearing no emergent setae in the type. In the average
neuropodium the setae are mostly six in number; these are coarse, with
subhastate heads the tips of which are curved, entire, and acute; the
surface appears smooth, the seriate spinules being exceedingly minute
and easily overlooked; pale straw colored. The notocirri have the
usual enlarged distal end baring a slender tip and a little exceed the
neuropodial setae. The elytra have an arrangement in general similar to
that normal in Halosydna so far as that usually goes, but twenty-four
pairs are present, these occurring on somites, II, IV, V, VII, IX,
XI, XIII, XV, XVII, XIX, XXI, XXIII, and XXVI, XXVIII, XXIX, XXXI,
XXXIII, XXXV, XXXVII, XXXIX, XLI, XLIII, XLV, and XLVII. The elytra
are characteristically widely imbricated so as completely to cover the
dorsum and prostomium. They extend out far laterally so as wholly to
overlap the parapodia proper though the ends of the setae and notocirri
extend beyond the edges. The elytra have the surface wholly smooth and
the edges are also not fringed. As preserved, the type has no definite
color markings; color greyish, the elytra of weak fulvous cast.
Length near 22 mm.; greatest width exclusive of parapodia, 2.8 mm.; to
ends of parapodia, 5 mm.; to ends of setae, 6.8 mm.
Taken as a commensal on a sea-urchin (Metz, July 20, 1911).
Type--M. C. Z. 2, 140.
_Lepidonotus setosior_ sp. nov.
Readily distinguished from _L. squamatus_, _coeloris_ and other
species recorded from the Pacific coasts of North and South America
by the greater length and coarseness of the notopodial setae, these
being stout pointed spines often nearly attaining the ends of the
neuropodials and thus exceeding the latter in actual length. The
notopodials, however, are obviously more slender than the neuropodials;
they are much more numerous than the neuropodials and form a dense,
subcylindrical, spreading group. The elytra are characterized by
bearing over their free portions numerous high and stout, conical,
hard or chitinous tubercles which are, however, much less dense than
the very different rounded eminences of _squamatus_, these cones often
roughened; between these high cones, and over the covered part of the
elytra as well, numerous small rounded tubercles or nodules; much more
slender and shorter, erect, conical papillæ present on the outer border
of at least some of the elytra but no truly ciliate fringe could be
detected in the types. The elytra are long, subelliptic in outline, and
are arranged either with axis nearly longitudinal or very oblique, the
most anterior elytra, however, subcircular. Eyes on each side unusually
widely separated, the anterior one low on side, a little ectocaudad
of base of anterior process. Anterior processes of prostomium about
four-fifths as long as the median ceratophore and much more slender.
Lateral tentacles much more slender than the median, and, exclusive
of the filamentous tip, falling short of attaining the middle of the
style of the latter exclusive of its tip; styles biannulate with black
as frequent, the basal process also black. Median tentacle surpassing
palpi in length; subapical swelling pronounced, much more so than that
of the laterals. Tentacular cirri and notocirri similar in form to the
median tentacle. Anal cirri proportionately somewhat shorter than in
_squamatus_. Color of venter and parapodia grey; elytra at present grey
over a fulvous ground. Setae dark amber to nearly ferruginous, darker
than usual in _squamatus_. A paratype has elytra fulvous of dilute
ferruginous cast with black mottlings.
Length, 18 mm.
Type--M. C. Z. 2, 141.
_Lepidonotus leius_ sp. nov.
A species characterized by its rather thin, easily detached elytra
which have their surface wholly smooth or, at most, showing a few
scattered minute points; closely fringed along the outer margin, about
the cephaloectal region, and for a short distance along the anterior
edge. Elytrophore attached cephaloectad of middle. Anterior and ectal
margins of a typical elytron only weakly convex, the cephaloectal
corner subrectangular though rounded; caudal margin strongly convex,
the inner end of elytron like the end of an ellipse but with lower
margin the more oblique. Elytra transverse or but little oblique,
strongly overlapping in the middorsal line. Prostomium of usual
general form. Eyes large and black, the anterior ones near middle
of main region of prostomium, the posterior ones closer together
and at caudal end. Only one tentacle, a lateral, retained in type.
This characterized by a short cylindrical style which to the base
of the distal swelling is scarcely longer than the basal process,
and especially by an unusually long slender tip which is as long as
the rest of the style. The parapodium of the first segment bears two
prominent setae in the usual position; tentacular cirri of usual form,
the filiform tips long, when bent back reaching proximad of middle of
style. Notocirri also characterized by their long terminal filaments.
Neuropodial setae light amber-colored; arranged in the usual vertically
elongate patch, presenting a narrow dorsal half and a broader ventral
one. In the ventral part of the patch normally four longitudinal rows
of three setae each, while the narrower upper region shows also about
four rows but with only two or one in each. The setae have the usual
general structure. Notopodials numerous, reaching beyond distal end of
neuropodia and sometimes nearly to middle of the neuropodial setae. In
the type the elytra are light brown. The tentacles and notocirri ringed
with black as common.
Length, 13 mm.; width exclusive of parapodia, 3 mm.; width to tips of
setae, 6 mm.
Dredged.
Type--M. C. Z. 2, 142.