[9] OLIGOCH^TOLOGICAL RESEARCHES. 887 



The pseudo comb-like spines are similar to the comb or fan-shaped 

 ones, but the membrane, between the prongs, is absent. It is evident 

 that the comb like and pseudo comb-like spines are only modifications, 

 one of the otlier. To the simply forked spines they are not closely 

 related. 



Ilyodeilus Perrieeii n. sp. 



The cephalic ganglion is about as broad as long, and its anterior end 

 is not broader than the posterior one (Fig. 3d). 



The efferent duct is shorter than the atrium and i)enis together, but 

 nearly of the same length as the atrium alone. The penis has no chiti- 

 nous sheath, is very short and conical, and pointed, gradually tapering 

 towards the apex. The oviduct is double, the interior one being chiti- 

 nous, extended, funnel-shaped and somewhat bent, gradually tapering 

 towards the exterior porus (Figs. 3e and 3/). The exterior oviduct is 

 intlated, sack -like, very broad at its base, and from here irregularly 

 tapering towards the exterior apex. It is surrounded by numerous 

 longitudinal muscles, which are connected with the body wall (Fig. 3e). 



The receptacle is bent, its top being sack-like and not globular (Fig. 

 3g) ; no spermatophores. The ovaries form two large bodies in the tenth 

 setigerous segment. The testes are comparatively small in the three 

 first segments behind the cingulum, or in the eleventh, twelfth, and 

 thirteenth setigerous segments. 



The integument is darker and thicker than in the following species. 

 The membrane between the prongs of the comb-like spines is very pellu- 

 cid and difficult to perceive. Both prongs are bent in the same direction. 

 The comb-like and hair spines are found all along the upper side of the 

 body (Figs. 3h; 3 i; 3 k). The integument is flesh-colored. 



Length of the body, 10"'"^ to 12"™ -, width of the same about l"""". The 

 anterior part is considerably the thickest, and from here the body tapers 

 gradually towards the posterior end (Figs. 3 a; 3 (7; 3 c). 



Rahitat. — Fresno County, California, in irrigation ditches sparingly. 

 In ponds in King's River more frequently met with. I have never found 

 this species much above the level of the prairie, or about 300 feet above 

 the sea. 



This species is easily recognized by the thickness of the anterior part 

 of its body. 



Ilyodrilus Sodajlis n. sp. 



Nervous system. — The cephalic ganglion is much broader than long, 

 the posterior margin being lined with several (6) ganglionic swellings, 

 of which the two on each side are globular. The two middle ones are 

 oval or conical, constituting the posterior apex of the ganglion (Fig. 5 0). 



Vascular system. — Xo differentiated pulsating hearts, only indistinctly 

 or weakly j^ulsating perigastric vessels, beginning in the ninth setiger- 

 ous segment and extending towards the cephalic lobe, one i)air in every 

 segment; but the nearer the cephalic lobe the smaller are the vessels 



