EXTERNAL CHARACTERS OF THE MUSTELID^. 



829 



and Lxdra. It is similar!}- hairy in a male Grisonella, but in a 

 female of the same species it is naked ov scantily hairy. It is 

 also scantily haiiy in MelUvora, Tayra, Taxidea, Meles, Me2)hitis, 

 and Gonepatus. 



In all eases examined the vulva is a fusiform excrescence with 

 a vertical slit-like orifice, bounded on each side by two labia 

 enclosing the clitoris and the urinary and genital orifices. (Text- 

 fig. 39, A-C.) 



Text-fie'ure 39. 



A. Anus and vulva of Co'%epatus prnteus. 



B. The same of Grisonella sp. from Cordova, Argentine. 



C. The same of Flesiogale midipes. 



The penis is very variable in shape, in accordance with the 

 shape of the hacidum ; but the prepuce is always situated well 

 in advance of the scrotum, as in the Canidfe, Procyonidfe, and 

 Ursidaj. 



The Classification of the Mustelidce. 



In the classification which follows I have adopted the method 

 employed by Gray of combining analytical headings, which give 

 prominence to particular characters, with the definitions ordinarily 

 found in the text-books, where the characters are set forth as if 

 of equal value. For the intei'pretation of the table it is necessary 

 to remember that contrasted headings are marked by the same 

 letter — e. g., a-a', b-b', and so on, I have adopted all the sub- 

 families originally proposed and defined by Gray and Gill, and 

 consistency in treatment has compelled the addition of several 

 new groups of that rank. It is not claimed that they are all of 

 equal value. The Gulonin^, for instance, have been admitted 

 rather as a concession to the opinion of a distinguished contem- 

 porary than as a mark of my conviction that the characters 

 deserve the rank assigned to them. Systematists of the old 



