418 Reviews — Prof. Edward D. Cope — 



cuboid and navicular bones. There were five toes on the bind feet, 

 in wbicb the terminal digits are compressed and sharp. On the 

 whole, in the limited number of incisor teeth it approaches the In- 

 sectivora ; it has many affinities with the Prosimiae and some affini- 

 ties with Lemurs, and is more distantly connected with the Carnivora. 

 The Creodonta differed from the Carnivora in the small size of the 

 limbs as compared with the head. Many of the species are thought 

 to have been aquatic. In Europe the group is represented by such 

 types as Arctocyon, which has commonly been regarded as a Marsu- 

 pial. In this suborder six families are included, comprising about 

 twenty-seven genera. Among these genera the author would look 

 for the ancestors of the existing Carnivora. The genera with marked 

 inner cusps and tubercles to the molar teeth are nearest to the 

 Marsupials. The genera without internal tubercles to the molars 

 are regarded as ancestors of the Hyaanodontidae ; the family Miacidaa 

 are the forerunners of the Dogs ; and the family Oxyamidse were 

 the forerunners of the Cats. It will thus be seen that this large 

 group is worthy of careful study. The genus Ictops agrees closely 

 with Didelphys ; but there are only three upper incisors, and the 

 angle of the mandible is not. inflected. Peratherhim agrees in dental 

 characters with Didelphys, and is only retained until the complete 

 dentition is known. Triisodqn is characterized by the simplicity of 

 the fourth inferior premolar, and the rudimentary anterior cusps 

 of the molar teeth ; from a study of its teeth the author concludes 

 that the posterior milk molar of Diphyodonts is a permanent tooth 

 in the Marsupialia. Four species exemplify the characters of this 

 type. JDeltatheriiim is a genus which has in the lower jaws two 

 tubercular sectorial teeth, and a third behind them with a long heel. 

 It has three premolars and a well-developed canine. The dentition 

 is similar to that of the Opossums. Didelphodus differs from Delta- 

 iherium in having an additional premolar in the lower jaw. 



Stypolophus is represented by ten species. S. viverrinus is about 

 the size of the domestic Cat. Its skull is remarkable for the lachrymal 

 bone not extending posterior to the large lachrymal foramen. The 

 genus is found in the Phosphorites of France, but the author does 

 not follow Gaudry in uniting it with Proviverra, because the fourth 

 upper premolar has an internal cusp and an external cusp, flanked 

 in front and behind by a basal heel. 



The Miacida? comprise two genera, Miacis and Didymictis. Miacis 

 is conspicuous for its canine characters, among which marsupial 

 affinities are said to be no more prominent than in the case of other 

 Creodonta ; while Didymictis makes an approximation towards 

 Oxycena in its dentition. It is well represented by seven species. 

 The Oxyaenidse comprise Pterodon, Protopsalis and Oxycena. Characters 

 of the skull are suggestive of Cats, but the head was larger and limbs 

 smaller than in true Carnivora, and they rather resemble the Car- 

 nivorous Marsupials in proportions. This type is supposed to have 

 been aquatic. Mioclcsnvs comprises about eight species, known 

 from their dentition, which affiliates the genus to Arctocyon ; but it 

 is distinguished by the single tubercle on the inner part of the crown 



