1897.] 



FROM SOUTH AFBICA. 



337 



either side of the male pores on segment xviii. The two spermi- 

 ducal pores of each side of the body are connected by a groove 

 which is a common feature of this genus. In the middle of the 

 groove on the xviiith segment lie the sperm-duct pores. On the 

 inside of this invariably are the two setae (both present) of the 

 ventral pore. All the species have penial setae. 



As is the case with all members of the genus Acanthodrilus, there 

 are two pairs of spermathecse lying in segments viii., ix., which have 

 at least one and sometimes more diverticula. 



The first species I name : — 



(1) Acanthodrilus purcelli, n. sp. 



The collection contained ten specimens of this form, which were 

 collected " under rotten logs in woods on the Newlands slope." 

 Only one of these ten was sexually mature ; this individual was 

 the largest of the series. It is a long, rather slender worm of a 

 dark coloration, showing also interference colours. It measured 

 170 mm. in length by 5 mm. in breadth. I counted 135 segments. 



The prostomium is " complete," i. e. it is continued by grooves 

 to the end of the first segment of the body. 



The ditellum is saddle-shaped, not developed all round the body, 

 but only dorsally and laterally ; it occupies segments xiii.-xvi. 



The setce are in eight series ; of these each two of the ventral 

 couple are nearer to each other than are the two of the lateral 

 couple. 



' I apply the term " incomplete" to a prostomium which is not continued 

 by furrows over the first segment, " complete " to one that is. 



