1176 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Terebella gracilibranchis Grube. 
Terebella gracilibranchis Grube, Annulata Semperiana, p. 230, pi. XII, fig. 0, 1878. 
These differ from Grube’ s description in that the tentacles are proportionately somewhat larger, 
and that the thirteenth ventral scute is much smaller than the twelfth, scutes 13-16 inclusive being 
very small and easily overlooked. All specimens small. Length to posterior border of twelfth scute 
4 mm. Breadth of anterior region 2.5 mm. Body swollen and filled with eggs. 
Genus LANICE Malmgren. 
Lanice flabellum Baird. 
Two imperfect specimens. I have identified them from the descriptions and figures of gills, ten- 
tacles, and setse given by McIntosh. (Challenger Report, vol. xii, p. 446, pi. xlix, fig. 3, pi. l, fig. 1, 
pi. xxvn A, fig. 22.) 
Collected at station 4101, on bottom of coral sand, shells, and foraminifera, in 143. to 122 fathoms. 
Lanice expansa, new species. 
A single specimen in tube. Tube 3 mm. in diameter, of a membranous base, with fragments of 
shells, corals, etc., covering entire surface. At apex it broadens into two kidney-shaped expansions, 
one on either side the opening. Cylindrical portion of tube attached at hilus (fig. 83). Greatest 
breadth of expansion 10 mm. Length, i. e., diameter parallel to cylindrical portion, 5 mm. Along 
edge a row of narrow, spiny protrusions having the characteristic membranous base with particles of 
foreign matter on the surface. Though the body of the animal apparently filled the tube it was found 
in it in an inverted position, with head pointing toward base of shell. This tube answers well to the 
description given by McIntosh (Challenger Report, p. 448) for a Terebella ( Lanice ) tube, and may be 
of the same species, though McIntosh found no part of the animal. 
Body incomplete, only about 30 somites remaining. Head with dorsally a rather prominent 
collar, the latter extending on either side to form a prominent lobe, ending in a blunt point. Seen 
from ventrally, the lobes are fused at base, their edges then overlapping for about half their length, 
then separate leaving a broad V-shaped space between the two sides. Edge of V not straight but with 
a blunt elevation about in the middle. Posterior and lateral to the collar is a smaller and less promi- 
nent lobe. 
Tentacles much coiled and twisted so that number and length are not easy to determine. A groove 
with elevated, much wrinkled margin runs along one side of each. On either side of this groove a 
comparatively broad band of pigment. Thorax anteriorly a little narrower than head, widening pos- 
teriorly to about same width as head. Ventral shields broadest anteriorly, gradually narrowing to 
sixth somite, then uniform in size to fourteenth, when they suddenly become larger and much more 
prominent. 
Three pairs of gills, first large, second about half size of first, third about half size of second. 
Each with a broad portion supporting a much branched apex. 
Setigerous somites 17. Setae long, gently curving to acute tip. Uncini in two rows, each uncinus 
with base prolonged into an acute point. One large tooth, with two rows of smaller teeth at apex, 
each row of 2 or 3 teeth. Middle tooth of upper row nearer apex than others, so that side view shows 
apparently more than 3 rows (fig. 84). 
Type no. 5225, U. S. National Museum, collected by the Albatross at station 4101, on coral sand, 
shells, and foraminifera, in 143 to 122 fathoms. 
Genus THELEPUS Malmgren. 
Thelepus branchiatus, new species. 
A single much mutilated specimen. Head with no trace of eyes, and bearing long deeply grooved 
tentacles. Branchiae in 3 rows. In first row about 8 on a side of long cirrus-like processes, extending 
considerably beyond head. Those of second row equal to these in size, but fewer in number. Of 
third row only one, on the left side, was retained. A very small cirrus on the right side probably 
