INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 623 



New Haven to Wood's Hole and Casco Bay, under stones in the 

 upper i)art of the fncus-zone, and nearly up to high-water mark. 



The above description was made from living specimens taken at Savin 

 Eock, near New Haven. 



Some of the specimens obtained at Wood's Hole appear to differ some- 

 what from this description, but the differences may be chiefly due to 

 their being taken in the breeding season. In these the anterior fascia 

 cles consist of two short setie, which are slightly curved in the form of 

 an italic/, and are subacute, not biiid at tips. At the ninth to twelfth seti- 

 gerous segments a thickening occurs, forming a clitellus; on the ninth 

 segment the setne are replaced by a small mammiform, bilobed organ;, 

 on the tenth there is a pair of prominent obtuse papilke, swollen at 

 base. On the posterior segments only two setse were observed in each 

 of the four fascicles, but they were longer, more slender, and more 

 curved at the tip than the anterior ones. In each of the segments 

 slender CDecal tubes, forming about two loops on each side, were no- 

 ticed. Length, about 35'"™. 



LuMBRicuLUS TENUIS Leidy. 



Marine Invertebrate Fauna of Rhode Island and New Jersej^, p. 16 (U5), Plate 

 11, fig. 64, 1855. 



Point Judith, Ehode Island, abundant about the roots of grasses on 

 the shore of a sound (Leidy). We did not obtain this species. 



Halodrillus Yerrill, genus no v. 



Body long and slender. Blood white or colorless. Setoe small, acute,. 

 in four fan-shaped fascicles on each segment. The alimentary canal 

 consists of a pyrlform pharynx, followed by a portion from wliich sev- 

 eral (five to seven) rounded or pyriform csecal lobes, of different sizes, 

 arise on each side and project forward and outward ; these are followed 

 by a large two-lobed portion, beyond which the intestine is constricted 

 then thickened and convoluted, and covered with polygonal, greenish, 

 glandular cells, which become fewer farther back, where the intestine 

 becomes a long, narrow, convoluted tube. In the anterior part of the 

 body, around the stomach and caecal lobes, there are numerous convo- 

 lutions of slender tubes. The blood-vessels running along the intes- 

 tine contain a colorless fluid. 



Halodrillus littoralis Yerrill, sp. nov. (p. 321.) 



Bod3^ round, slender, moderately long, tapering to both ends, but 

 thickest toward the anterior end, tapering more gradually posteriorly. 

 Head small, conical, moderately acute, or obtuse, according to the state 

 of contraction -, mouth a transverse, slightly sinuous slit beneath. The 

 setae commence with four fascicles on the first segment behind the buc- 

 cal ; the setfe are slightly curved, forming rounded, fan-shaped fascicles 

 of four to six setfe, the middle setae being longer than the upper and 

 lower ones J posteriorly the set^e are less numerous. Caudal 



