CREODONTA. 
87 
and plantigrade. As to the Qiiaclmmana, man himself is a pentadactyle 
plantigrade Bunodont. * * Such a hypothetical type might be expressed 
by the name JBunotheriidcs, with the expectation that it will present subor¬ 
dinate variations in premolar, canine, and incisor teeth. The premolars 
might be expected to differ in the degree of development of the internal 
lobes, the canine in its proportions, and the incisors in their number.” 
The history of discovery of the Eocene forms of this order is briefly 
told. Professors Leidy, Marsh, and myself had described Creodonta as 
Carnivora, until I pointed out, in some remarks before the Philadelphia 
Academy (published December 22, 1875), their true relations. The first 
species of Tillodonta was described by Leidy from an inferior molar from 
New Jersey in 1868. Dr Leidy next described the dentition of the man¬ 
dible of the same genus from Wyoming. Subsequently, Marsh described 
the superior molars of an allied genus, also from Wyoming. In 1874, the 
writer described the dentition of the Taniodonta from specimens collected 
in New Mexico. In March, 1875, Marsh proposed the Tillodonta as an 
order of Mammals, giving its dental characters, and stating that the 
brain was “small”. In December, 1875, in his remarks on Creodonta, 
Professor Cope referred this group to the Insectivora as a suborder. 
In March, 1876, Marsh gave a full description of the cranial characters 
of the genus TUlotherium, describing the characters of the brain from a 
cast of the cranial cavity. In the same month of 1876, the wu’iter 
characterized the suborder Treniodonta, referring to it the genera Ectoganus 
and Calamodon. 
CREODONTA. 
The genera of this suborder found in the Wahsatch beds of New Mexico 
differ as follows: 
I. First and third inferior true molars without internal cusp; last superior molar 
longitudinal; last inferior molar carnassial. Ambloctonus. 
II. Inferior caruassials with interior tubercle; no tubercular molar; last superior 
molar transverse: 
Three tubercular carnassials... ShjpolopJms. 
Two tubercular carnassials.... . Oxycena. 
III. Inferior carnassial with interior tubercle; a tubereular molar: 
One tubercular carnassial. Didymictis. 
The number of toes on the hind foot cannot be certainly stated in all 
