568 OLIGOCHAETA 



diverticulum. Penial setae not attenuated at extremity, where there are a few denticu- 

 lations generally bifid. Hab. Togo. 



This species again is very like the three that have been just described ; the only 

 difference that can be gathered from MICHAELSEN'S description is in the form of 

 the penial setae and in the fact that there is only one kind of them. 



(15) Benhamia togoensis, MICHAELSEN. 

 B. togoensis, MICHAELSEN, loc. cit., p. 260. 



Definition. Leng/k, 60 mm.; breadth, 2^ mm.; number of segments, 140. The setae anteriorly 

 more strictly paired than posteriorly, and smaller. Their form is, so far as we know at 

 present, unique among the Acanthodrilidae in that they are ornamented with numerous Jiiie 

 denticles. The penial setae are ornamented after the same fashion as the ordinary setae. 

 Hab. Togo. 

 This species is easily distinguishable by the presence of ornamented setae upon 



the segments of the body. There is no other species of Benhamia in which this 



ornamentation of the setae has been met with. 



(16) Benhamia inermis, MICHAELSEN. 

 B. inermis, MICHAELSEN, loc. cit., p. 209. 



Definition. Length, 600 mm.; breadth, 10 mm. ; number of segments, 350. Clitellum, 

 XIII XX, saddle-shaped. Male pores npon a circumscribed area, the pores of segment 

 XIX somewhat nearer together than those of segment XVII. Genital papillae, eight 

 pairs in front of the clitellum on the grooves between segments IX-XVI in front of the 

 ventral setae ; one pair upon segment VIII just to the outside of the spermathecal pore ; 

 behind the clitellum two papillae on the left side between segments XX/XXII, and one 

 pair between XIX/XX ; on the clitellum three pairs, one between XVI/XVII ; the next 

 to the outside of these on XVII, followed by a pair on XVIII corresponding in position 

 to the last. Dorsal pores commence XII/XIII. Gizzards in V, VI ; calciferous glands 

 in XI, XII, XIII. Spermathecae have (apparently) no diverticula. Penial setae 

 completely absent. Hab. Togo. 



This species is nearly unique among its genus for the absence of penial setae ; the 

 only other species in which these setae, so characteristic for the genus Benhamia, 

 are absent, is Triyaster lankeateri. B. inermis is the largest of Acanthodrilids. 



