STUDIES ON EAETHWOEMS. 83 



I was unable to see either the pores of the sperm-ducts or 

 those of the spermathecse, but on dissection I found that the 

 sperm-duct opened to the exterior in the anterior region of 

 somite xx slightly dorsad of the ventral couple of setse on each 

 side (fig. 12, d). 



The spermathecse open close to the nephridiopores in the 

 anterior region of somites vii, viii, ix, on each side. 



Internal Anatomy — All the septa are thin and easily 

 torn ; the nephridia are delicate, but the spermathecse are very 

 prominent (fig. 14). 



The alimentary canal (fig. 14) consists of six well-marked 

 regions. The thin-walled buccal region occupies two somites, 

 and leads into the pharynx, which extends very nearly up to 

 the end of somite v. There is nothing specially noticeable 

 about these parts ; the muscular wall of the pharynx does not 

 extend so far backwards on the ventral as it does on the 

 dorsal surface. This seems a more or less usual condition in 

 Earthworms. The oesophagus, which follows, is somewhat sac- 

 culated and is bent forwards upon itself in somite vi, and after 

 another bend back again, enlarges ip somite vii to form a 

 proventriculus, such as is found in Lumbricus, but which 

 is not so well marked in other Earthworms. Owing to the in- 

 fuudibulate septa, the oesophagus appears to extend through 

 more somites than it actually does, but by carefully tracing 

 the nephridia (for the septa are very thin and easily broken 

 and therefore not reliable for the purpose) it is found that the 

 gizzard (e) occupies somite viii. This has the ordinary 

 structure with the chitinous lining within and the nacreous 

 muscular appearance without. Behind the gizzard commences 

 the tubular intestine (^), which is continued through somites 

 IX to XV ; this is narrower than the oesophagus and quite 

 straight ; it is hidden by the seminal reservoirs in the somites 

 in which these structures lie. In each of the somites ix, x, and 

 XI is a pair of intestinal glands (fig. 14,/), similar in shape 

 to those figured by Perrier for his genus Urochseta,^ and 

 called by him "glandes de Morren.^^ Each of these six 



' ' Arch, de Zool. Experini. et gener.,' iii, 1874. 



