344 DR. ST. G. MIVART ON THE ARCTOIDEA. [A-pr. 21, 



"Subfamily Procyonina (confined to America). 

 " No alisphenoid canal. 

 " True molars on each side g. 



Procyon. Cercoleptes. 



Nasua. Bassaris. 



" Subfamily Mustelina (of general geographical distribution). 

 "No alisphenoid canal. 

 "True molars on each side g. 



Arctonyx. Grisonia. 



Meles. Gal era. 



Taxidea. Vison. 



Mydaus. Mustela. 



Mephitis. Maries. 



Oulo. 



Helictis. Lutra." 



Mellivora. 



The distinctions and observations of Mr. Turner have been further 

 developed and perfected by Professor Flower in his elaborate paper 

 on the Classification of the Carnivora ^ wherein the principal cranial 

 characters of nearly all the Arctoid genera are described, with figures 

 of the skulls of Ursus, Putorius, Procyon, and Bassaris (figs. 1, 2, 

 3, 3a, and 4), and their points of agreement are summed up as 

 follows^: — " They all agree in having the intestinal canal without 

 a csecum, all other known Carnivora ' possessing this appendage. 

 Moreover they all agree together, and differ from all other Carnivora, 

 in the structure of the generative organs of the male, facts of con- 

 siderable value in determining affinities. They all have a large penis, 

 vyith a very considerable bone, vehich is usually more or less curved, 

 somewhat compressed, not grooved, dilated posteriorly, and often 

 bifurcated, or rather bilobed, in front. They are all destitute of 

 Cowper's glands. All liave the prostate rudimentary, or consisting 

 only of a thickening of the wall of the urethra and forming no di- 

 stinct prominence, 



" Among all the diversity in the characters of the base of the 

 cranium, especially in the form of the auditory bulla, the following 

 points of general agreement are to be found : — 



"(1) The cavity of the bulla is simple (compared with Felis). 

 That is, although there are frequently trabeculse or partial septa 

 passing mostly transversely across the lower part, and generally 

 connected with the tympanic ring, there is no distinct and definite 

 septum dividing it into a separate outer and inner chamber. In all 

 cases, on looking into the external auditory meatus (in the dried 

 skull when the membrana tympani is removed) the opposite wall of 



1 P. Z. S. 1869, p. 4. ' L. c. p. 14. 



' Subsequently Prof. Flower discovered that the csecumis absent in JVa«(fmia. 

 It may also be entirely absent in Arcticiis. 



