DESCRIPTIONS OF EARTHWORMS. 81 



into the gizzard, shows a wider portion, a specimen of proven- 

 triculus. This portion of the digestive tube is situated in front 

 of the first thickened septum (5th), so the gizzard appears to 

 belong to the fifth segment, though lying much farther back- 

 ward. The tubular intestine then following is furnished in 

 segment 6 , 7 and 8 on each side with a large , dark coloured, 

 intestinal gland. Perrier found in his specimen the gizzard 

 situated in segment 6 ; intestinal glands are not mentioned 

 by him. 



The main truucs of the vascular system consist of a 

 dorsal, a ventral and a supra-intestinal vessel. The dorsal 

 vessel is a single tube , which communicates with the ven- 

 tral trunc by six pairs of commissural vessels in segment 

 3 to 8; in segment 9, 10 and 11 three pairs of large 

 abdominal hearts (fig. 1, ah) are situated, arising from the 

 supra-intestinal vessel, which in the following segments be- 

 comes visible on the dorsal surface of the intestinal canal. 

 In this region the dorsal trunc shows a series of large 

 ampullae, and communicates with the supra-intestinal vessel 

 by small vertical vessels, arising from its ventral side. The 

 ampullae of the dorsal trunc are described and figured by 

 Perrier; he found only four pairs of commissural vessels 

 in segment 7 — 10. 



Of the genital organs only the pairs of vesiculae 

 seminales (fig. 1 , vs) could be recognized ; they are not 

 very large and attached to the posterior side of the ante- 

 rior septum of segment 10 and 11. Perrier found them 

 in the 11th and 12th segment. 



The nephridia resemble somewhat those of Microchaefa 

 (fig. 3). They consist of a great number of brown-coloured 

 tubules , situated in a longitudinal row close to one another; 

 each tubule forms a loop , the two limbs of which are spirally 

 wound round each other. The whole set of tubules is united 

 by connective tissue and attached to the end of a wide 

 glandular tube , forming a loop which consists of a short 

 limb that descends and a long one that ascends along the 

 row of tubules ; the ascending limb forms another U-shaped 



Notes from tlie Leyden jMuseum, Vol. X^III. 



6 



