194 The Alligator and Its Allies 



voluted for a short distance, but gradually 

 straightens out, to pass to its posterior end as 

 a nearly straight duct. The anterior straight 

 portion of the oviduct is connected with the head 

 of the ovary by a narrow band of mesentery. 



Each testis, Fig. 55, b, like the ovary, lies along 

 the vent ro -mesial border of its corresponding kid- 

 ney and is connected with the posterior region 

 of the cloaca by a slender vas deferens, Fig. 55, c, f . 



According to Rathke (in C. acutus] a small, 

 slender epididymis lies along the outer side of the 

 posterior half of each testis. 



The Copulatory Organs. The penis, Fig. 56, usu- 

 ally lies completely hidden in the cloaca; with its 

 glans projecting backwards it is strongly arched; 

 along the convex side of the arch, which is directed 

 towards the upper wall of the cloaca, runs a groove, 

 which serves as a penial urethra to conduct the 

 semen. 



According to Rathke there may be recognized 

 in connection with the penis two fibrous strands 

 (resembling the corpora cavernosa of mammals), 

 a corpus cavernosus urethrea, and a covering 

 derived from the mucous membrane of the cloaca. 

 The two fibrous strands arise from the pubis as two 

 thick plates that soon completely fuse together by 

 their adjacent sides to form the shaft, c, of the 

 penis. These fused strands taper gradually to- 

 wards the glans, in which they end in a point. 

 From their mode of fusion there is left between 



