ZooL.— Vol. II.] RISEN— OLIGOCHMTA. 207 



preservation the genital zone is less distinct than it would 

 have been in well preserved specimens. The zone is large 

 but not deep, and is bounded by the edges of the saddle- 

 shaped clitellum, which barely reaches the ventral side of 

 the body. The two longitudinal fossae could hardly be 

 distinguished. 



Gizzards. — The gizzards are fully developed but shorter 

 than in Trigaster Lankesteri, as described by Benham. The 

 thick part is situated in the posterior part of the somites. 

 From the thick posterior part the gizzard tapers anteriorly 

 into a very thin wall. 



The tubular intestine is much nipped by the septa. There 

 are no traces of any calciferous or other diverticles of the 

 intestine and there appears to be no typhlosole. The walls 

 are deeply plicated and strongly vascular. 



Glands. — There is a row of narrow but rather long sub- 

 pharyngeal glands opening into the ventral part of the 

 pharynx. This row extends all along the ventral side to 

 the oesophagus. The septal glands are very small and 

 easily overlooked. 



Nervous System. — The brain is in somite III. The 

 ventral nerve-cord is very large. Its muscular outer layer 

 is enormously developed, its diameter being thicker than 

 the inner cellular part. 



Nefhridia. — There is a pair of perfect meganephridia in 

 each somite. The nephropores are in line with setse b. 

 Judging from sections the nephridia seem to resemble those 

 of JVotiodrilus. 



SpermatheccB. — There are two pairs of large spermathecas 

 in VIII and IX, each possessing a large sac-like diverticle 

 of peculiar structure. This diverticle is directed forwards 

 and is situated in the same somite as the main sac. In one 

 spermatheca the diverticle is formed by the bulging out of 

 the whole anterior wall of the lower, narrower part of the. 

 spermatheca; in the other the diverticle is attached to the 

 narrow part of the spermatheca proper, at its junction with 

 the body-wall. The diverticle and the distal sac proper are 



