80 
BUNOTHERIA. 
11 . 
Since 1872, the Eocene formations of the Rock}^ Mountains’ have 
been known to contain the remains of nninerons species of Mammals 
which possess greater or less proportions of characteristics of the order 
Quadriimana. Some of these were referred by their first describers to the 
Insectivora^ and others to the Ungulata. In October, 1872, the writer 
described a genus, Anaptomorplius, represented by a jaw found in the 
Bridger beds of Wyoming, in whose dentition Quadrumanous character¬ 
istics are so marked as to have induced me to comj)are it with such t^q^ical 
forms as Simia. The characters of the mandibular dentition then recorded 
are those of the true monkeys, but the permanent separation of the man¬ 
dibular rami, distinguishes the genus from these and from the marmosets, 
constituting a resemblance to the lemurs. The dental formula is I. 2 ; C. 
1; P. M. 2 ; M. 3 ; the crowns of the premolars with a single, undivided, 
compressed tubercle. In the following year, I published (May G, 1873) 
a second paper, in which the characters of Anaptomoj'plius and of the 
earlier described TomWierium (Cope) w'ere more fully elaborated. In this 
essay, I referred*’ the latter genus also to the Qiiadrumana, but as express¬ 
ing a type even more aberrant than the Lemurs, and therefore well sepa¬ 
rated from the true Monkeys. I cited, as reasons for this reference, the 
flat ilium, the long femur, the round head of the radius, the form of the 
distal end of the radius, with the coossified symphysis and four transverse 
incisors of the lower jaw. I pointed out that the forms of the molars are 
similar to those of the Quadrimana, and to animals of some other orders 
as well, while the number of molars is greater than in the Lemurs, or 
any other known group of the order. The formula of the mandible is I. 
2 ; C. 1 i P. M. 4; M. 3. I also pointed out the resemblance between 
this genus and Ilyopsodus, which was then estimated as Ungulate, but 
whicli has since been stated to bo Lemurine. Finally, I added to this 
series, in the same year,! the genus described by Leidy as Notliarctus^ and 
a. fourth species, which belongs to the genus Pantolestes, Cope. 
* On the Priniitive Types of the Mammalia Ecliicabilia. 
t Annual Report U. S. Geol. Sure. Terrs., 1872 (pub. 1873), p. 519. 
