I466 CLASS MAMMALIA. 



an apparently allied form from the North American Eocene said 

 to have only three premolars. In Pelycodus the hallux was not 

 opposable. There are a number of other names which have been 

 applied to American forms of uncertain position, but since the 

 synonymy is very complex nothing would be gained by quoting 

 them here. 



Family Lemurim:. — Passing to Lemuroids more closely allied 

 to existing forms those extinct genera may first be noticed many of 

 which exhibit the generalised feature of having four premolars in 

 either jaw, on which grounds, coupled with certain slight differences 

 in the form of the lower premolars, Dr Schlosser regards them as 

 constituting a distinct family — the Adapidcs. We may, however, 

 provisionally follow Professor Flower in including them in the Lemu- 

 ridce, of which they will form the subfamily Adapince. The best 

 known of these forms is the type genus Adapts (Aphelotherium, or 

 Palceolemur), from the Upper Eocene (Oligocene) of both France 



and England, in which the dental formula is I. -, C. -, Pm. -, M. - • 



2143' 



the upper molars being of a quadritubercular type. The last upper 

 premolar is as complex as the true molars, which (fig. 1349) re- 

 semble those of Lepidolemur and 

 Hapalemur, while the skull makes 

 the nearest approach to that of 

 Propithecus. It has, indeed, been 

 suggested that this and the allied 

 genera show certain relationships 

 to the Anthropoidea which are not 

 seen in existing representatives of 



Fig. 1349- —Palatal aspect of the left upper the Suborder I but their alleged re- 

 cheek-teeth of Adapts magna; from the . , ° . 

 Upper Eocene of Hampshire. MlOnship tO the DUnodont ArtlO- 



dactyla does not appear to be sub- 

 stantiated. The imperfectly known genus Ccenopithecus from the 

 Upper Eocene of Switzerland is regarded by Dr Schlosser as iden- 

 tical with Adapts, although Professor Riitimeyer considers that it is 

 allied to the American Pelycodus. From the Eocene of North 

 America we have the two nearly related genera Tomitherium and 

 Notharctus. The former (with which Limnotherium of Professor 

 Marsh is identical) is distinguished by the single roots to the pre- 

 molars, and by the development of a third lobe to the last lower 

 true molar. Notharctus agrees with Adapts in the presence of two 

 roots to the premolars, but has a larger lower canine. Thinolestes 

 and Telmatolestes are probably allied to or identical with the pre- 

 ceding genera ; both being from the American Eocene. 



Turning to the more typical representatives of the family, in which 

 at least the upper premolars do not exceed three, we have the small 



