428 PROCEEDINGS : BOSTON SOCIETY NATURAL HISTORY. 
46. Thelepus crispus sp. nov. PI. 17, figs. 175-1786. 
Form rather stout, not greatly tapered posteriorly; thorax pass¬ 
ing gradually into abdomen; tapered considerably towards prosto- 
mium from tenth somite. Number of somites 88-147. 
Prostomium with ample dorsal flap, transversely corrugated on 
dorsal surface ; no eyes. 
Peristomium with circlet of strongly grooved tentacles. 
Pranchiae (Fig. 175) three pairs, branching from the base in 
numerous, slender, spirally curled filaments; borne on somites 2-4. 
Setae begin at third somite and extend to penultimate in young 
specimens; to fourteenth from pygidium in older ones ; with stri¬ 
ated limb on each side; sometimes slightly bent (Figs. 176, 177). 
Uncinigerous tori begin at fourth somite; uncini absent from 
extreme end of body. Uncini (Figs. 178 «, b) single-ranked from 
fourth to seventh somites, inclusive, and gradually returning to this 
condition towards end of series; in flattened rings from eighth 
somite. (“ rangee parabolique,” Clapar&de) onward. Tori attain 
their greatest length between the twelfth and twenty-fourth 
somites ; thence diminish very gradually to end of body; those of 
the abdomen rounded and wart-like. 
Length of large female specimen, 270 mm.; greatest transverse 
diameter (at sixteenth somite), 13 mm.; dorso-ventral diameter, 
12 mm. 
This fine Terebellid is represented in the Columbia University 
collection by a single large female turgid with eggs. It occurs on 
the California coast as far south at least as San Francisco, and is 
abundant at Bolinas, Marin County. Its tube is formed of coarse 
sand or gravel. It frequently harbors commensal individuals of 
Polynoe insignis , and northward, probably also Harmothoe tuta (see 
p. 394). 
Sabellidae. 
47. Bispira polymorpha sp. nov. PI. 17, figs. 179-183. PI. 
18, figs. 184, 185. 
Form nearly terete, dorsum flattened in adult specimens; in 
young specimens, form slender; tapered gradually at posterior end 
to a minute pygidium; anus terminal. Somites, 170 or more. 
Thorax (Fig. 179) of nine somites, one sixteenth to one ninth of 
entire length (exclusive of branchiae) according to degree of con¬ 
traction and probably also the age of the specimen. 
