206 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
THELEPUS Malmgren. 
Thelepus crassibranchiatus, n. sp. 
Head not especially prominent, with row of very numerous eye-spots just under the lobe of its 
disk (fig. 69). Tentacles very thick, about as long as first ten body segments. Four on a side. Branchiae 
in two transverse rows on second and third seg- 
ments (counting the head as first). Those of 
second segment five straight thick filaments in a 
transverse row on either side, more or less fused at 
their bases (Jig. 70). Branchiae of third segment- 
similar to those of second, but each composed of 
only three filaments on a side, filaments more 
delicate and not more than three-fourths as long 
as anterior gills. Capillary setae begin on third, 
uncinate on fifth segment. Posterior portion of 
body broken, but apparently both kinds of setae 
are present on all segments. Uncinate setae with 
one strong terminal tooth and two laterally placed smaller teeth (fig. 71). On the thorax each segment 
is marked with parallel lines, forming a rectangular plate (fig. 69). 
Family AMPHARETIILE. 
AMPHICTEIS Grube. 
Amphicteis nasuta Ehlers. 
Amphicteis nasuta Ehlers, Annelids of the Blake, p.232, pi. 49, figs. 1-6. (Ehlers’s plate is labeled “ Ampharete.” From the 
context, this is evidently a misprint. ) 
A single specimen, labeled “Sta. 6055, Aguadilla,” evidently of this species, though the charac- 
teristic palese of the second segment had been lost. Only the 14 anterior segments were preserved. 
Family AMPHICTENIDAi. 
PECTINARIA Lam. 
Pectinaria gouldii Verrill. 
Cistenides gouldii Verrill, Invert, of Vineyard Sound, p. 612, pi. 17, figs. 87, 87a. 
Pectinaria belgica Gould, Invert, of Mass., 1841, p. 7. 
P. auricoma (Grube) Leidy, Invert. Fauna of Coasts of R. I. and N. J., 1855. 
P. groenlandica (Grube) Stimpson, Marine Invert. Fauna of Grand Manan, Smithsonian Contributions, vol. 6, 1854. 
Cistenides gouldii Webster, Annelida Chsetopoda from Provincetown. 
Pectinaria gouldii Verrill, New England Annelida, pt. 1, p. 287, U. S. F. C. Rept. for 1880, p. 731. Andrews, Annelids from 
Beaufort, N. C., p. 297. 
These are larger than the specimens described by Verrill, reaching a length of 64 mm. From 
Ensenada Honda, Culebra, and station 6055. 
Family CAPITELLM. 
DASYBRANCHUS Grube. 
Dasybranchus umbrinus Grube. 
Dasybranchus umbrinus Grube, Annulata Semperiana, p. 189. 
Collected from stations 6061, 6062, 6066, and Boqueron Bay. v 
Dasybranchus lunulatus Ehlers. 
Dasybranchus lunulatus Ehlers, Annelids of the Blake, p. 174, pi. 45, figs. 5 to 9. 
Collected from Puerto Real and Arroyo. 
With these I have included, rather doubtfully, two small specimens from station 6061 and one 
from station 6055, which seem to me to be probably the young of this species. They differ from 
Ehlers’ diagnosis in that 16 segments bear capillary setse, the last three, however, being very delicate. 
69 
Figs. 69-71 .— Thelepus crassibranchiatus. Fig. 69, Anterior 
portion, x 20; e. s.,eye spots. Fig. 70, Branchia of second 
segment, x 13. Fig. 71, Uncinate seta, x 428. 
