896 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [18] 



The principal characteristic of the species is the enlargement of the 

 lower end of the penis. 



LiMNODRILUS MONTICOLA n. Sp. 

 (PI. XI, Fig. 10.) 



Ner'oous system. — The cephalic ganglion is nearly square, the posterior 

 lobes well rounded but not much projecting (Fig. 10c). 



Generative system. — The generic organs are comparatively minute. 

 The lobes of the prostata are not globular and not much elevated, the 

 whole gland being larger and more compact than in the preceding- 

 species. The penis is nearly cylindrical, and only slightly widening 

 toward the exterior truncate end. The penis sheath is also cylindrical, 

 slightly widening toward both extremities. Its exterior end is not 

 deflected, sometimes rather the contrary. The penis and penis sheath 

 are of the same length. The oviduct is double. The interior one 

 is chitinous and resembles closely the penis sheath, being only wider 

 but not much longer. Its lower extremity is sometimes deflected and 

 plate-like, especially in ver^'^ matured specimens (Figs. lOe and 10/"). 



The exterior oviduct is, as usually, sack-like. Its upper part covers 

 the interior oviduct closely ; its lower end is wider, with plainly visible 

 cell nuclei. The receptacle is straight, sometimes constricted at the 

 middle, generally found containing spermatophores of usual shape (Figs. 

 10^ and lOh). 



The spines are very slender, curved, the upper prong of the fork 

 slightly the longest (Fig. 10c). 



The length of the body 30"™.; width of the same 0.75"'" (Fig. 10«). 



Habitat. — California, Sierra Nevada, at Seven Spriug Meadow, on the 

 east side of the North Fork of King's Ei ver. Numerous specimens found 

 in or between decaying wood submerged in the water. AltiKide about 

 9,000 feet. 



The principal characteristic of the species is the cylindrical form of 

 the penis and its truncate end. The other species of the genus have 

 the extremity of the penis either globular or pointed, or present other 

 forms easily recognizable. 



LiMNODRILTJS ALPESTRIS 71. Sp. 

 (PL XII, Fig. 11; PI. XVII, Fig. 11; PI. XVIII, Fig. 18.) 



Nervous system. — The posterior part of the cephalic ganglion is the 

 broadest, sometimes furnished with three well- rounded lobes. The 

 swellings of the ventral ganglion are almost circular. In not fully de- 

 veloped specimens the cephalic ganglion is two-lobed (Fig. 91a). 



Generic' system. — Of the generic organs, the i»enis and the oviduct tire 

 comparatively longer th an in .any other species of the genus. The lower 

 extremity of the penis is slightly swelled and pointed. The jienis sheiitli 

 is trumpet-shaped at both extremities, the exterior one being the widest. 



