240 ' PUERCO FAUN^. 



We can distinguisli three families among our Eocene forms of lemu- 

 roids, in the dental characters, as follows: 



Inferior premolars, four Adapida. 



Inferior premolars, three Mixodectidce. 



Premolars, two, with internal lobes in the upper jaw Anaptomorphidte. 



The genera of the Adapidce have already been considered (p. 215).* I 

 therefore compare the genera of the two remaining families. 



MiXODECTIDiE. 



a. Last premolar without inner tubercle. 

 A very large incisor; canine smaller; first premolar, only one-rooted Mixodectes. 



aa. Last premolar with internal tubercle. 



A very large t canine; first premolar only one-rooted Microsyops. 



A very large t canine; first and second premolars each one-rooted Cyodontomys. 



Anaptomorphid^. 



Inferior incisors two; canine small ; premolars two-rooted Anaptomorphua. 



Inferior premolars one-rooted Necrolemur. \^\ 



The correct nomenclature of the large tooth in the front of the mandi- \A i 

 ble of the genera of Mixodectidce is not yet ascertained. It may be a canine 

 or an incisor. I will also remark that in the genus Necrolemur of Filhol the 

 characters of the superior premolars are not yet completely known. 



MIXODECTES Cope. 



Proceed. Amer. Philos. Soc.,1883, i). 447. 



Char. Gen. — The position of this genus is uncertain, but may be near 

 to Cynodontomys Cope, which I have provisionally placed among the Pro- 

 simian t It is known from mandibles, which have presumably the following 

 dental formula : I. 0; C. 1; Pm. 4; M. 3. An uncertainty exists as to the 

 proper names of the anterior teeth, which cannot be decided until the dis- 



• From that synopsis must be omitted the genera now placed in other families, Microtijopi ond 

 AnaptomorphuK, anA Pan/o/cj^f* (Artiodactyla). Omomyt must be placed in the section with four pre- 

 molars, in tlin place of Pantolestee. 



tPaU'ontologicul HuUotin, No. 34, p. 151. 



