232 



DR. W. B. BENHAM ON 



[Nov. 15, 



examination of the surface, owing to the strongly contracted state 

 •of the worm : the nephridiopores, however, are in line c. 



Text-fig. 48. 



^TP. 



A. B. 



JRJiododrilus eduUs.—V entval view (X about 3) of clitellai- region, showing male 

 pores ( (J ) and arrangement of tubercula pubertatis (T.P.) ; A B [a 6 in tlie 

 text], the chsetal rows. Segment 16 is unfortunately drawn a little too large. 



Interned Anatomy. 



The body-wall is of great thickness and the septa behind 

 segments 7 to 12 are very stout. 



The dorsal vessel is single ; the last heart in segment 1 3, and 

 rather smaller ones in 10, 11, and 12. 



The gizzard, in segment 5, is large, with thick walls, and 

 contains stones. There is no oesophageal gland, nor any dilata- 

 tion. The intestine commences in the 17th segment, where the 

 gut suddenly enlarges to twice its previous diameter. 



The worm is meganephric, and the nephridia commence as far 

 forwards as segment 3. Each nephridium (text-fig. 49) consists 

 of a bunch of 3-5 loops ventrally (situated in line a-b), whence a 

 long dorsal loop passes upwards to a point about midway between 

 c d, and a straight duct leaves the same bunch, and passes to the 

 body- wall just below c, at which point no doubt it opens 

 externally. 



There is, in addition, a blind csecum or bladder with muscular 

 wall, which extends almost to the mid-dorsal line : the exact 

 connections of it I have not determined. 



The nephridiostome is small. 



