4G2 On Two new Earthioormft. 



7 mlllim. Tliis is proportionately longer than the penial setas 

 of any other member of the genus except B. si/hestris, whicli 

 species, as I have already mentioned, comes very near to 

 B. tangnnyikce. The proportions of the length of tlie penial 

 setie and the total length of the body are, in fact, roughly the 

 same, about one-ninth. 



The penial seta is not only very long, but it is very thin ; 

 at the basal end, where it is embedded in the sac, the 

 thickness is hardly, if at all, greater than that of the 

 ordinary seta? of the body. The diameter gradu illy diminislies 

 to the other, free, extremity of the seta, which is not more 

 than one-fourth of the diameter of the thicker end. Coinci- 

 dently with this gradual diminution in thickness is an alteration 

 in colour. The embedded end of the seta is of a horn-yellow ; 

 the free extremity is perfectly colourless. The actual tip of 

 this seta is strongly hooked. For a very short distance before 

 its termination the seta is spirally twisted in a way which is 

 very common in this genus. This region of the s -ta has a 

 few irregularly arranged and sharp spinelets, whose paints 

 are directed towards the extremity of the seta. It is obviously 

 only in details that the penial seta of B. tanganyihe differs 

 from that of B. syJvestris. But this particular j)attern is not 

 iincon:mon in Benhamia ; and after all the spiral twisting 

 and the apparently fewer spinelets distinguish the penial seta 

 irom that of its close ally B. syJvestris. 



The sperraathecEB are two pairs and lie in segments viii 

 and ix. They show some differences from those oi' B.sylvestris 

 as figured by Michaelsen. The pouches themselves are very 

 large and thin-wallcd and their distinction from the thick- 

 walled duct is thus very evident. The latter is long and 

 coiled, not simply bent twice as in B. sylvestris ; it is also 

 more slender than in that species, and thus appears longer. 

 The duct appears to be quite as long as the pouch. The end 

 of the duct where it opens on to the exterior is rather wider. 

 The diverticulum is single and spherical. It is connected by 

 a duct of its own length, which is narrow, with cither the end 

 of the pouch or the beginning of its duct. It is a little 

 difficult to say which, for the pouch narrows rapidly but 

 gradually into the duct. The region, however, into which 

 the diverticulum opens is thick-walled and nacreous in 

 aj)i)earancc, so we may, perhaps, regard it as the duct. 



1 shall now extract from the foregoing account of the 

 structure of Benhumia ianganyikw the reasons which lead me 

 to regard it as a new species distinct from its obviously near 

 ally B. sylvcstris. They are the following: — 



