ORGANS OF THE SUM ATE AN KHINOCEROS. 109 



being longer in proportion to its depth, and its apical expansion narrower across in 

 proportion to its height (-J inch to 1^), with its margins, moreover, somewhat crinkled. 

 It is, in conclusion, interesting to observe that the distinctness of the two genera 

 Rhinoceros and Ceratorhinus, as shown by other characters — external, cranial, and vis- 

 ceral — is confirmed by these differences in the sexual organs. 



DESCRIPTION OF THE PLATE. 



PLATE XX. 



Fig. 1. Glans penis of Ceratorhinus sumatrensis, of about the natural size, viewed 

 from above, with the lobes artificially extended, to show better their form 

 and attachment. 



Fig. 2. The same, viewed from the side. 



Fig. 3. Outline of glans penis of Rhinoceros indicus, after Owen (Trans. Zool. Soc. iv. 

 pi. ix. fig. 6). 



