Wortman — Studies of Eocene Mammalia. 23 



Art. II. — Studies of Eocene Mammalia in the Marsh 

 Collection, Peabody Museum ; by J. L. Wortman. 



[Continued from vol. xvi, p. 368.] 



Suborder Anthropoidea. 



In a previous part of the present work, I have given the 

 characters by which this suborder is distinguished from the 

 Cheiromyoidea and the Lemuroidea. I have likewise proposed 

 and defined three divisions of the Anthropoidea, of which Tar- 

 sius and its allies constitute the first (Paleopithecini), the liv- 

 ing marmosets the second (Arctopithecini), and the remaining 

 higher Primates the third (Neopithecihi). Of the twelve or 

 more species of the Anthropoidea now known to occur in the 

 Bridger, the organization of at least three can be determined 

 with some degree of satisfaction from the material now at hand. 

 This information is not limited to any one part, but includes 

 nearly every portion of the skeletal structure. It is reason ably 

 clear, therefore, that these three species are primitive members 

 of the Neopithecine division of the Anthropoidea. In like 

 manner, the skull of the Wasatch species — the so-called Anap- 

 tomorjphus homunculus — is sufficiently complete and well pre- 

 served to show that it is a very near relative of the living East 

 Indian Tarsius. and hence a member of the Paleopithecini. 

 The remaining nine or more species from the Bridger are 

 represented mostly by teeth alone, and it is therefore not an 

 easy matter to decide correctly to which of the three groups 

 these forms belong. 



As regards the Arctopithecini, or the living marmosets, our 

 knowledge is confined almost exclusively to the existing species. 

 It has been already noted that some of their characters are 

 unique among the Primates. Whether the lack of opposa- 

 bility of the pollex and hallux is to be looked upon as a degen- 

 eration from a former more perfect condition of prehensility 

 of the extremities, or whether it represents a stage in the 

 process of acquirement of the opposability of these digits, can 

 not now be determined. It is worthy of note, however, that 

 the internal cuneiform and the proximal end of the articu- 

 lating metapodial resemble the corresponding parts of the 

 lemurs and monkeys much more than those of any other ani- 

 mal ; and, notwithstanding the lack of opposability, this like- 

 ness would be sufficiently close to indicate their ordinal position 

 did we know the marmosets from their skeletons alone. There 

 are at the same time some peculiarities in the make-up of these 

 bones, which would lead the cautious anatomist to hesitate in 

 pronouncing upon the opposability of the hallux, especially if 



