30 ZOOLOGICAL EESULTS OF THE RUWENZOEI EXPEDITION. 



POLTTOREUTUS GRANTI Beddavd. 



Polytoreutus granti Beddard, P. Z. S. 1907, p. 420. 



In describing some years since * several species of this genus from East Africa, I 

 found among a collection from Mt. Kenya two closely allied species, which, however, 

 were plainly to be differentiated upon a careful study. It is interesting to find upon 

 Euwenzori the same presence of two closely allied species of Polytoreutus, not — it may 

 be remarked — specially related to their congeners of Kenya. To find closely related 

 species in the same comparatively restricted area is rather more remarkable than would 

 have been the existence of more remotely allied examples of the same genus. This 

 species, which I have named after Mr. Ogilvie-Grant, F.Z.S., comes nearer to Poly- 

 toreutus kirimaensis than does P. rmvenzorii. It is represented by a single specimen, 

 not fully mature as to the clitellum, but apparently quite fully mature as to the 

 sexual organs. One of the two copulatory chambers and the penis were protruded. 

 The size and the external characters generally agree with those of P. ruwenzorii. 



The worm is a trifle more slender. The clitellum was not developed, and upon the 

 segments to be included in it I observed no deficiency of setae such as occurs in 

 P. 7'uwenzorii. The relations between the distances which separate the two setce of 

 each pair are much as in P. ruwenzorii. In the same way I observed a long tube 

 of chitin to be extruded from the nephridiopores. I do not like to assert positively 

 that there is a difference between the two species in the segment which contains the 

 first pair of nephridiopores. But in the present species I noted a pair of these 

 apertures in the third segment, i. e. a segment further forwards than I observed the 

 same pores in P. ruwenzorii. The internal anatomy seems to agree with that of 

 P. ruwenzorii and other species of Polytoreutus in the alimentary canal with its 

 appended calciferous glands and in the situation of the last heart (eleventh segment). 

 It may be mentioned, however, that P. granti, like P. ruwenzorii, has the dorsal 

 vessel doubled in the twelfth segment. This doubling of the dorsal vessel is known 

 in the genus Polytoreutus — for example, in P. gregorianus f . 



The male organs of reproduction are much like those of P. ruwenzorii, and yet show 

 difi^erences in minutise. As in that and other species of the genus, there is but a single 

 vas deferens on each side, ending in front in an elongated chamber (" Samenmagazine ") 

 behind the funnel. The sperm-sacs are but a single pair. They are elongated and 

 not so markedly thin anteriorly as in P. ruwenzorii and other species. The right-hand 

 sac, as in that species, is longer than the left, but the difference is not quite so 

 pronounced. The length of the longer sac is 21 mm. The two sacs are not joined at 



* " On some new Sx)ecies of Earthworms belonging to the Genus Polytoreutus, &c.," P. Z. S. 1902, vol. ii. 

 p. 190. 



t Beddard, P. Z. S. 1901, vol. i. p. 191. Michaelsen has not referred to the condition of the dorsal vessel 

 in the species with which the present is particularly compared. 



