CHARACTERS OF PALEOCENE VERTEBRATE FAUNA 



388 



(2) The Multituberculates are nearly related to those of the Lance, 

 formation, but the species of each phylum are larger and more special- 

 ized. The placentals have apparently no predecessors in the Lance; at 

 least this is true, in my judgment, of the bulk of the placental fauna and 

 so far as the present evidence indicates. The Lance mammal fauna is 

 so fragmentary that statements about its composition should be carefully 

 qualified. 



(3) The reptiles are chiefly Chelonia., Crocodilia, and Choristodera. 

 One snake has been recorded; lizards were present, although not re- 

 corded. No dinosaurs are present;* the marine reptiles of the Mesozoic 

 would not be expected. The reptiles all belong to families that originated 

 in the Cretaceous (Belly Eiver) or earlier. Three of the families still 

 survive, one disappeared with the Eocene, another with the Pal eocene. 

 The dominant Tertiary families of Chelonians (Emydidge and Testudi- 

 nidse) are not present, appearing first in the Lower Eocene. The absence 

 of Tertiary types of lizards and snakes is of little weight, as it may be 

 merely a matter of defective record. 



List of typical Paleocene Vertebrate Faunas 





Puerco. 



Torrejon. 



Clark 

 Fork. 



REPTILIA 



Order Testudines 



Fam, Baenidae (Cretaceous-Eocene) 



Baena escavaria Hay 



Fam. Dermatemydidse (Cretaceous-Recent) 



Hoplodielys crassa Hay 



" saliens Hav 



X 



X 

 X 

 X 



X 



X 

 X 

 X 



X 



X 

 X 



X 



V 



.... 



" paludosa Hay 



AJfG,fYios€fYi'us fiul) stt'iato, Hav .. 



.... 



Fam. Trionychidje (Cretaceous-Recent) 



Co7ichochelys admiralnlis Hay 



Aspideretes saqatus Hay 





" piiercensis Hay 



" singularis Hay 



Order Choristodera 



Fam. Champsosauridse (Cretaceous-Paleocene) 

 Champsosanrus anstralis Cope 



.... 



" saponensis Cope 



Order Serpentes 



Fam. ? ? Crotalidse ( ? ? Cretaceous-Recent) 



Helagras prisciformis Cope ® 



Order Crocodilia 



Fam. Crocodilidee (Cretaceous-Recent) 



Grocodilns stavelianus Cope ® 







■ ^ N 



.... 



*But see appendix, p. 400. 



5 Generic and family reference needs revision. 



«The generic position of these Eocene and Paleocene cro 



codiles is wholly doubtful. 



