888 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [10] 



and the weaker the pulsations. No dermal vascular system. The gas- 

 tric secoiidar}' vessels are rectilinear. One perigastric and one gastric 

 vessel in every segment. The perigastric vessel is branched, and situated 

 behind the latter near the posterior margin of the segment. m\ 



Generative system. — The efferent duct is about one and a half times 

 longer than the atrium and copulative organs together ; its width is 

 about the same as in the other species of this genus (Fig. 5g). Atrium 

 is very short and broad, nearly crescent-shaped (Fig. 5 g), and the apej 

 of the penis is globular and very much larger than its base, ^o penij 

 sheath. The oviduct is single, bell or cone like, the lower or exterio] 

 end being the widest. The whole organ is full of small spiculse, some 

 what similar to those found in the same organ of Psammoryctes iimbelU 

 far.* The testes are situated in the 10 setigerous segments, beginning 

 in the twelfth and extending to the twenty-second setigerous segment 

 The ovaries are found in the nineteenth to the twenty-second segment 

 entirely covered by the testes. The receptacle (Fig. 5 h) is somewhat 

 irregular, has two main sack-like lobes,supported on a short narrow 

 stem, at the base of which is found a comparatively large accessory 

 gland (Fig. 5 7t, gl.). 



Numerous perigastric cells of a circular form, and containing numer 

 ous globules. The spines are of three kinds, viz, hair spines, forkec 

 spines, and pseudo comb like spines, the latter with no membrane be 

 tween the prongs. The prongs themselves, however, have their innei 

 surface striated (Figs. 5 e and 5 f). 



Similar or nearly similar spines are found in Ilyodrilus fragilis. Th« 

 forked are somewhat similar to the above, but the prongs are not ser 

 rated (Fig. 5c and M). 



The length of the body is about 25"'™; the width of the same about 

 jmra Qp more. The integument is reddish-flesh colored. 



Habitat. — California, San Francisco, in a vspring emptying into th« 

 Marine Hospital lake. I have not found the worm in the lake itself. 



Ilyodrilus sodalis is a very distinct species, characterized by its 

 cephalic ganglion, receptacle, efferent duct, and pseudo comb-lik( 

 spines. Its copulative organs are extremely pellucid. 



Ilyodrilus Fragilis n. sp. 



(PI. V; Figs. 4a to f?.) 



Nervous system. — The cephalic ganglion is longer than or as long as 

 broad, cordate, with the posterior end considerably narrower than th< 

 anterior part (F'ig. 4c). 



Generative system. — The efferent duct is longer than the atrium, bn 

 not longer than the atrium and penis together. The atrium is shortei 

 and thicker than in the preceding species; the penis is longer than in 



* Vejdovsky, Zeitscli. f. w. Zoolozie, Bd. xxvii, page 137. 



