1885.] DR. ST. G. MIVART ON THE ARCTOIDEA. 357 



and strong, sharp-pointed and much curved. The palmar and 

 plantar surfaces are naked. 



There are 14 dorsal, 6 lumbar, 3 Siicral, and 26 caudal vertebrae. 

 Tlie dorsal region is relatively shorter, and the lumbar and tail 

 longer than in any other Arctoid. It has the relatively shortest 

 first lower true molar. There are small rudimentary clavicles. 

 The inner condyles of the humerus may or may not be perforated \ 



To the characters already pointed out by Professor Flower''' may 

 be added the conspicuousness of the stylo-mastoid foramen and the 

 flattened, broadened-out condition of the basis cranii external to it. 

 The palate is not prolonged as in Procyon and Nasua, behind the 

 molars, a peculiar pointed process projecting backwards from its 

 hinder edge behind each last molar. 



Strong postorbital processes project both from the frontals and 

 the molars. The alisphenoid is' widely separated from the ])arietal 

 by the wide junction between the squamosal and the frontal. The 

 palatine also joins the orbitosnhenoid. Tiiere is a very large infra- 

 orbital foramen. The palate is very slightly arched, with an antero- 

 posterior convexity. The lachrymal foramen is placed very low in 

 the orbit. 



The mandible differs greatly in shape from that of any other 

 Carnivore, and much resembles that of the Lemuroid, Microrhynchus, 

 The inferior margin of its horizontal ramus is concave ; the symphysis 

 is very long, and the postero-inferior part of the mandible is greatly 

 expanded, the angle projecting downwards as well as backwards. 

 There is no subangular process. The coronoid process is much 

 prolonged upwards, and may sometimes incline a little forwards 

 rather than backwards. 



Comparing this most arboreal Arctoid with Arctictis, the most 

 arboreal ^luroid, one is struck with the similarity which exists 

 in the proportional length of the limbs, and in the presence of the 

 chevron bones beneath the tail, of which there are here seven. 



The ultimate phalanges are more elongated and curved than 

 in Procyon and Nasua ; but there are no large bony plates to sheath 

 the bases of the claws as in the Cats, nor have the penultimate 

 phalanges the feline lateral excavation. 



Molar formula =P. |, M. |. 



The molars are very simple in structure, with low flat crowns, 

 though essentially like those of the two preceding genera. The 

 fourth upper premolar and first upper molar are formed on the same 

 type as those of Procyon, but the cusps are much less developed. 

 The second lower molar is rather smaller in comparison with the 

 first one than is the case in Nasua and Procyon. The other lower 

 molars are formed on the same type as those of the two last-mentioned 

 genera, but are more flattened on the surface and less tuberculate. 



' Sir Eicbard Owen (in his Anat. of Vertebrates, vol. ii. p. 509) says :— "I 

 have seen the condyle notched in the right, and perforated in the left 

 humerus." 



2 P. Z. S. 1869, pp. 9, 10. 



Proc. Zool. Soc— 1885, No. XXIV. 24 



