129 



times larger, the efferent duct arising from its anterior part. Spermi- 

 ducal funnel small ; length about twice the diameter. Spermathecae 

 with o\'al expanded ampulla near ectal end; diminishing in diameter 

 toward ental end ; rosette of four glands at ectal opening ; spermathecse 

 unite dorsad of digestive tract to form a short oval tube through which 

 they communicate with lumen of alimentary canal in the posterior 

 part of V. 



The characters of the pcnial bulb are discussed on a later ])age. 



Described from ii sexually mature specimens. Type and para- 

 types in the collection of the writer. Paratypes also in the collection 

 of Professor Frank Smith. 



The specimens which are the basis of this description were found 

 in late March, 191 1, near Urbana, Illinois, in rich soil, under decay- 

 ing leaves in undisturbed forest land. All of the specimens are sexu- 

 ally mature, showing spermatozoa in the spermathecae, well-developed 

 egg masses in the body cavity, and developing spermatozoa in XI. 



AMnities. — It is somewhat difficult to determine the systematic 

 relations of this species owing to the fact that some of the species 

 which are included in the genus are quite incompletely described. 

 Species which, so far as described, seem to be closely related, might, 

 if more thoroughly worked out, reveal characters which would sep- 

 arate them widely. However, until these meager descriptions are 

 supplemented by further study, one must be content to place each new 

 species in what seems to be its natural position. If the minimum num- 

 ber of distinct differences be considered, this species seems to approach 

 about equally H. gemmata Eisen, H. ochracea Eisen, and H. dorsalis 

 Bretscher, but as these are imperfectly described, the assumption of 

 this relationship must be tentative. H. geuiiiiata Eisen differs from 

 H. moderata in the characters of the setae, the spermiducal funnel, the 

 nephridia, the brain, and the spermathecae ; H. ochracea Eisen differs 

 in the characters of brain, nephridia, and spermatheca^ ; and H. dor- 

 salis Bretscher shows dift'erences in length and in the character of the 

 brain. 



EXTERNAL CHARACTERS 



The body is slender and has an average length of about 16 mm., 

 the extremes being 13 and 19. In transverse section it is circular. 

 The diameter is greatest in the region of the clitellum, where it aver- 

 ages about 0.48 mm. ; posterior to the clitellum the diameter diminishes 

 only to a ver}- slight degree. In living specimens the body is opaque 

 and whitish yellow. The prostomium (PI. VIII, Fig. 6) shows a 

 slight but gradual tapering. The intersegmental grooves are quite 



