BY E. J. GODDARD. 327 



of excretion dependent upon them. They occur abundantly in 

 close connection with the blood sinuses, which perhaps is of 

 further significance. 



Connecting the ventral and dorsal body walls are masses of 

 dorsi-ventral muscle fibres. In the posterior region behind the 

 stomach these muscles are more obliquely arranged, and constitute 

 the bulk of the body substance. 



One can differentiate between a group which runs on either 

 side of the pharynx, and others more laterally situated. Those 

 situated on either side of the pharynx in places form the lateral 

 boundaries of the ventral lacuna; in other regions they divide 

 that lacuna into median and lateral divisions. In effecting this 

 division they do not form continuous sheets, but occur as bundles, 

 an arrangement which may be of metameric significance. 



Sinuses and coelome. — Possibly no Leech presents more interest 

 than Glossiphonia in the study of the coelome and its remains. 

 That the sinuses represent the remains of a coelome, is prettily 

 borne out by the occurrence in these channels of large nucleated 

 cells which in every probability represent the remains of a 

 coelomic epithelium, as pointed out by Bourne. These elements 

 do not occur in the vessels, and thus additional weight is given 

 to this argument. 



The details of the system of sinuses agree very closely with 

 those of other species, and call for no special remark, owing to 

 Oka's work in that connection. 



Digestive canal. — The mouth is situated in the anterior portion 

 of the oral sucker, and lies in the third somite of the body, which 

 is the position most common in other species. The mouth leads 

 dorsally into the pharyngeal sac. The wall of this sac is folded 

 and its lumen circular in cross-section. The anterior region of 

 the sac runs from the mouth to the central portion of the central 

 portion of the body-substance, and thence extends backward 

 through the brain-mass. 



The proboscis lies within the pharyngeal sac, and extends 

 through the greater part of its extent, occupying the area of 

 about twenty annuli. The posterior region of the proboscis 



