600 OLIGOCHAETA 



logically, to the spermathecae of other Oligochaeta, this view is established on a 

 surer footing. 



Nemertodrilus has two pairs of testes occupying the usual segments viz. x and 

 xi. Opposite to these are the funnels of the sperm-ducts ; these are large and much 

 folded, but there is no dilated region of the sperm-duct immediately following them, 

 as there is in other Eudrilids, such as E-udrilus. The spermiducal glands are two 

 tubular organs as in other Eudrilidae ; their muscular covering is but slight ; the 

 tube is lined by the glandular epithelium found in most earthworms ; but there is 

 no specialization into a glandular and a non-glandular portion ; the two sperm-ducts 

 of each side unite only at their actual orifice into the spermiducal gland, which 

 occurs, as in nearly all Eudrilids, at a little distance from the caecal extremity of 

 the organ. 



The integument is entirely without the epidermic sense organs, which are so 

 distinctive a feature of several genera. 



Nemertodrilus griseus, MICHAELSEN. 

 N. griseus, MICHAELSEN, JB. Hamb. wiss. Anst., vii, 1890, p. 17. 



Definition. Length, 120 mm.; breadth, i\ mm.; number of segments, 278. Nepkridia open 

 in front of ventral setae. Anterior septa rather stouter than those which follow. 

 Hal. Quilimane. 

 The appearance of the worm is, according to MICHAELSEN, very like that of a 



Nemertine, frequently occurring in the German coasts, Linens yesnerensis of O. F. 



MULLER. The colour is ' mouse-grey,' darker on the back than below, often verging 



towards a greenish olive tint. MICHAELSEN'S specimens were all collected at Quilimane, 



East Africa. 



Genus LIBYODRJLUS, BEDDARD. 



DEFINITION. Setae strictly paired. Clitellum complete, (XIV) XV -XVI. Male 

 genital pore between segments XVII/XVIII. A single median spermathecal 

 sac, communicating with the exterior on segment XIII, forming a ring round 

 the oesophagus, and again round the nerve-chord. Fenial setae present. 



This genus was described by myself a year or two ago, from specimens received 

 from Lagos, West Africa ; it contains, at present, but one species, L. violaceus. 



The first intersegmental septum separates segments iv/v ; the septa which lie 



