[6] OLIGOCH^TOLOGICAL RESEAKCflES. 883 



is the thickest, the body gradually taperiug towards the posterior end. 

 The color of the body is fleshy, brownish red, rather opaque, with the 

 vascular system plainly visible. 



Setae are found, as usual, in the family, in four fascicles in every seg- 

 ment, every fascicle containing numerous, or from eight to fifteen, 

 spines. These are in adult specimens entire, considerably curved, and, 

 generally speaking, not unlike those found in Encliytrceidw. In young 

 specimens the spines are found to be indistinctly forked (Fig. Id). 



Habitat. — California, Sierra Nevada, in Fresno and Tnlare Counties, 

 at an altitude of from 6,000 to 10,000 feet. 



It lives in the marshy meadows, and is sometimes found in dec aying 

 wood, sometimes again in the bottom mud, most frequently where the 

 water is very shallow. In small hollows, where manure has been de- 

 posited, this worm is most certain to be found ; in poor ground it will, 

 with certainty, be looked for in vain. 



This worm is decidedly of a nightly habit. In day-time it is never 

 found above the ground, but in night-time its tail is always seen pro- 

 truding in the water above the same. 



Adult specimens found in August and later. 



II.— Suh-fam. TUBIFICINI. 



KEY TO THE GENERA. 



I. — More than one kind of spines present, viz, hair spines, comb-like 

 spines, and forked spines, two of which kinds are always present (except 

 Hemitubifex.) 



A. The cephalic ganglion anteriorly furnished with a large conical processus. Sperma- 



tophores extremely long and spirally coiled. Oviduct single. 



Spirosperma. 



B. The cephalic ganglion is not furnished with an anterior processus. Spermato- 



phores short and broad, not spiral. 

 a. The efferent duct is comparatively short and broad, not longer than the atrium 

 and copulative organs together. 



Ilyodrilus. 

 6 The efferent duct is comparatively long and narrow, always longer than the 

 atrium and copulative organs together. 

 1. The base of the receptacle is furnished with glands. Efferent duct or 

 atrium furnished with a (a and c) " vesicula seminalis." Hair spines 

 and forked spines, but the former not always present. No comb-like 

 spines. The middle part of atrium is glandular. 



Hemitubifex. 

 2. The base of the receptacle is not furnished with glands; a "vesicula 

 seminalis " present. The middle part of the atrium not glandular. 

 Three kinds of spines always present, 



PSAMMORYCTKS. 



3. The base of the receptacles not furnished with glands. No " vesicula 

 seminalis." Two kinds of spines always present, viz, haii' spines and 

 forked spines. 



TlJBIFEX. 



