AND PERITONEAL CANALS IN CHELONIA. 439 



contained in the corpora cavernosa might be transmitted by the 

 peritoneal canals into the little conduits of the glaus, thence into 

 the cavity of the cloaca. They therefore held that the little con- 

 duits of the glans were the terminal branches of the peritoneal 

 canals. 



They had previously stated that in Testudo indica* the conduits 

 of the glans terminated near the summit of the clitoris ; but from 

 their experiments on E. trijuga they found that the orifice of the pe- 

 ritoneal canal terminated nearer to the base of the clitoris than to its 

 summit ; and they mention that the position of the opening in E. tri- 

 juga is intermediate between what they observed in Testudo indica 

 and its position in the crocodile, but more resembling the latter, in 

 which the peritoneal canals open at the base of the glans. They 

 ai'rived, therefore, at the following conclusion — that the peritoneal 

 canals in the tortoise and the crocodile divide at their extremity 

 into two branches, one going to open into the cloaca, and the 

 other tending towards the corpus cavernosum. But according to 

 Is. Greoffroy St.-Hilaire and Martin, there was this important phy- 

 siological difference — that the second branch opened into the ca- 

 vity of the corpus cavernosum in tortoises, whilst it terminated 

 in a cul-de-sac in the crocodile. I observe that Professor Owenj' 

 states that the peritoneal canals of the crocodile, besides commu- 

 nicating with the corpus cavernosum, open outwardly upon papillae 

 situated on each side of the base of the penis and clitoris, thus 

 conforming, according to his view, with the structure of the tor- 

 toises as described by Is. G-eoffroy St.-Hilaire. 



Having lately directed my attention to these remarkable diver- 

 ticula from the peritoneal cavity, and finding that my observations 

 on their structure do not agree altogether with either those of 

 Cuvier, Is. Geoffrey St.-Hilaire, or Owen, I shall here record a few 

 of the examinations I made on some species of different genera and 

 of both sexes. Before doing so, I may mention that Is. Geoffrey 

 St.-Hilaire used mercury for his injections ; but the membrane 

 lining the walls of these diverticula is so delicate, and mercury so 

 heavy and penetrating, that I am not surprised at the results 

 which he obtained. In injecting the canals I have used only water 

 coloured with a solution of carmine. I was most careful not to 



* They were not perfectly satisfied with the identification of the species, 

 but state that the subject of their observation was one nearly allied to 

 T. indica. 



t Comp. Auat. vol. i. p. 433. 



