OCR Text |
Show 1897.] FROM SOUTH AFRICA. 337 Ac. arenarius ... Ac. arundinis ... Ac. sclateri Ac. excavatus ... Ac. falcatus Ac. africanus Ac. photodilus ... Ac. lucifuga _ a Prostomi i Inc.1 IS Compl.1 Inc. n Compl. »» 1 I - 1 '3, P4 + + 0 -r- 0 + 0 0 + Spermathecas. 2 diverticula. JJ >> 1 diverticulum. »> 2 or 3 diverticula. 1 diverticulum. >» ti Gizzard. Large. Feeble. Large. Feeble. »> Large. it n 1 3' 3 a o 65 45 170 48 70 49 81 70 - Sperm-duct funnels. X., XI. X., XI. X. X. X. X., XI. X. X. X. either side of the male pores on segment xviii. The two spermiducal 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 seta3 (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 spermathecae 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 log3 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 m m . in length by 5 m m . 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 clitellum 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. 1 I apply the term " incomplete " to a prostomium which is not continued by furrows over the first segment, " complete " to one that is. |