NEW SPECIES OF OCNERODRILUS. 269 



The seta of the inner couple in this somite are both 

 present (fig. 68). There are no spermatheca. 



Ovary in xiii and oviduct in somite xiv. The inner 

 opening of the oviduct is found in somite xiii, close to 

 the ovary. It is of less rounded form than in Ocncro- 

 driliis Beddardi. 



The nephridia are much smaller than in any other 

 species, and occupy only about one-fifth of the whole 

 width of the somite, while the nephridia in most other 

 species are very large, occupying the larger part of the 

 somite, the upper part of the nephridium of O. Beddardi 

 covering the whole width of the somite from septum to 

 septum. Those in front of and in the clitellum, except 

 the one in somite ix, are not surrounded by any peritoneal 

 cells. Those posterior to the clitellum are furnished with 

 a few such cells along the upper part of the nephridium, 

 the long, slender lower part being entirely free. The 

 quantity of such cells varies greatly with maturity of the 

 individual. In many specimens they are hardly traceable, 

 in others they are more prominent, but never to such an 

 extent as is the case in any of the other species, where 

 this glandular covering is most copious. As a rule, in 

 the sexually mature worms the peritoneal cells are more 

 numerous. In younger worms of O. occidentalis I could 

 find no trace of them. The nephridium in somite ix is 

 always at sexual maturity furnished with peritoneal cells, 

 but only along its upper part. This is in analogy with 

 the development of the nephridia in Ocnerodrilics Bed- 

 dardi, where the nephridia in somite ix are larger than 

 any others anterior to the clitellum. 



The alimeiitary canal offers the same characteristics as 

 in the other species, but the anterior portion is much more 

 contracted and shortened. Thus the pharynx is more 

 globular, and the oesophagus and the tubular intestine 



