364 DR. ST. G. MIVART ON THE ARCTOIDEA. [Apr. 21, 



the external characters of this well-known genus \ comprising its 

 three or four species, all exclusively Palsearctic. As to the skeleton, 

 there are 14 or 15 dorsal, 5 lumbar, 3 sacral, and about 18 caudal 

 vertebrae. 



The dorsal region I have found to be longer relatively than that 

 of any other Carnivore, being most nearly approached by that of 

 Ictonyx and Conepatus. 



To the cranial characters already given by Prof. Flower ", it may 

 be noted, in addition, that the development of the sagittal ridge 

 very much approaches that of Ailuropus. The infraorbital foramen 

 is as large as in Ailurus. The postorbital processes are small as 

 always hitherto, except in Bassaris and Bassaricyon. The palate 

 extends as much behind the molars as in Proci/oti, but is narrower 

 there than inNasua. The pre- and postgleuoid processes are so de- 

 veloped as to bold the mandible in their grasp. The frontal sinuses 

 produce a prominence on the cranium ; and the ethmoid is much 

 more voluminous than in the previously noted form, and is even 

 more voluminous than in Canis, though not so prolonged. The 

 premaxilla does not attain the frontal. 



The transverse processes of the lumbar vertebrae are little deve- 

 loped, much as in Ailurus ; liut there are very large hyperapophyses 

 on the laminse of the cervical vertebrae. The scapula is very nearly 

 a right-angled parallelogram approaching a square. The ridges 

 and condyles of the humerus are much produced, more so than in 

 Nasua ; and the metacarpals are stouter than in any form yet 

 noticed. 



Molar formula = P. \, M. \. 



4' 2 



The first upper and lower premolar, however, are quite minute and 

 often fall away. The molars differ from those of any ^luroid, 

 Cynoid, or Arctoid yet described in the great preponderance in size 

 of the first upper molars over the fourth premolars, both above and 

 below. 



The first two upper premolars are much like the same teeth in 

 Procyon and Nasua. The fourth is rather more sectorial than in 

 those two genera, because there is only one internal prominence 

 made of two very small internal cusps, with one developed from the 

 internal cingulum as in the third upper premolar of Ailurus, only 

 much less developed and distinct, so that they soon wear down into 

 what is apparently the one prominence just spoken of. Of the 

 three external cusps, the middle one greatly preponderates. This 

 tooth has a superficial resemblance to the same tooth in Para- 

 doxuriis, Herpestes, and especially Bassaris. 



The first upper molar is different from any tooth of any other 

 Carnivore, but most resembles the same tooth of Ailuropus. It 

 has two equal-sized external cusps in front, with two small external 

 cusps behind. One large (especially long) internal cusp, obscurely 



1 I may be permitted to mention that I found the palmar surface naked ; 

 but the back of the tarsus was hairy, and naked surface narrow backwards to 

 an acute termination. 



2 P. Z. S. 1869, p. 11. 



