Marsh Collection^ Peabody Museum. 199 



and (6) that there is such a general similarity in the structure of 

 the limbs that one could easily have been derived from the other. 



The main points of difference are not of a fundamental 

 character, but relate to the assumption of modernized features, 

 such as (1) increase in size of the brain ; (2) development 

 of tympanic into a large, two-chambered, otic bulla, with 

 consequent modification of the contiguous cranial foramina 

 and paroccipital process ; (3) decrease in relative size of the 

 lumbar vertebrae; (4) reduction in size of the deltoid crest 

 of the humerus ; (5) union of the scaphoid, lunar, and centrale 

 of the carpus ; (6) loss of third trochanter of the femur, and 

 reduction in size of the lesser trochanter; (7) development of 

 cnemial crest of tibia, and (8) grooving of astragalus and 

 loss of fibular contact with the calcaneum. These characters, 

 as we know from so many other lines, pertain to all the primi- 

 tive Carnivora, and involve just such parts of the osteological 

 structure as have been profoundly and progressively modified 

 by development. Instead, therefore, of offering any difficul- 

 ties in the way of the derivation of the Viverrinse from 

 Viverravus, they are of such a nature as one would reasonably 

 assume to belong to the primitive type. The evidence, then, 

 in favor of this derivation, as it at present stands, is strongly 

 presumptive if not absolutely demonstrative. If well founded, 

 it establishes for this phylum an antiquity greater than that of 

 any group of living Carnivora thus far known. 



The position of the genus Oodectes with reference to the 

 living forms is not so clear. The possession of three true 

 molars in the superior and inferior series would hardly have 

 been expected in a Bridger representative, seeing that in Viver- 

 ravtts they had already been reduced to the modern formula 

 as early as the Torrejon. The genus, therefore, can clearly have 

 nothing whatever to do with the ancestry of the Viverra series. 

 That it is viverrine in its affinities, however, is so strongly 

 suggested by almost every feature of its structure that it 

 cannot be consistently placed in any other group. Among 

 living forms, it seems to bear a more decided resemblance to 

 certain of the Paradoxures than to any other section of the 

 family, although the relatively short, thick premolars, with the 

 disposition to the development of internal cusps, recall very 

 forcibly certain members of the Herpestinse. This character, 

 however, is also found in the Paradoxures. In the inferior 

 premolars it is important to note that in their lack of develop- 

 ment of a distinctively trenchant and sectorial character, they 

 are well fitted to give rise to the various types of teeth of this 

 group, even including members the most aberrant and highly 

 modified in this respect ; as Arctogcde and Arctictis. Indeed, 

 the skeletel parts, as far as they are preserved, show many 

 significant resemblances to the Binturong. These are 



