242 



OLIGOCHAETA 



repeated here (woodcut, fig. 43) ; within this brown ovoid body the lumen of the 



nephridium divides into two channels, 

 which give off a few branches ; these, 

 however, are not represented as anastomos- 

 ing ; the presence of this modified section 

 of the nephridium affines the two genera 

 in question to the Naids and to the Lum- 

 briculidae. Although this glandular body 

 is only properly developed in the two 

 genera mentioned above, there are traces 

 of it, according to STOLC'S figure (3, Tab. ii. 

 fig. 2), in, at any rate, one species of 

 Limnodrilus, viz. L. claparedianus ; in 

 this worm the lumen of the nephridium 

 immediately following the funnel is wider 

 than it is behind and in front of this 

 point, and is at the same time somewhat 

 tortuous in its course (woodcut, fig. 43, B 4) ; 

 there is, however, no network. The two 

 genera, liyodrilus and Bothrioneuron, are 

 further to be distinguished by the fact 

 that in neither of them is there an ampulla 

 such as occurs in Limnodrilus and (even 

 more prominently) in Spirosperma ferox 

 (EISEN, 12, PI. ii- fig- 2g. + ) ; this ampulla 

 is found in many earthworms. 



NEPHRIDIUM OF ILTODKILUS (A) AND 

 LIMNODEILUS (B). 



After Stole. 



i. External pore 2. Vesicle. 3. Peritoneal coat. 

 4, 5. Glandular body. 6. Funnel. 7. Ampulla. 

 8. Muscular bands. 



I 



Genus TUBIFEX, LAMARCK. 



Syn. Lumbricus, O. F. MULLER (in part.). 

 Saenuris, HOFFMEISTER. 

 Strephuris, LEIDY. 

 Blanonais, GERVAIS. 

 Nais, OKEN. 



DEFINITION. Dorsal seta-bundles with capilliform, pectinate, and uncinate setae ; 

 ventral bundles with uncinate setae only. Dilated hearts in the eighth segment. 

 No chitinous penis. 



