30 A REVISION OF THE COTYLOSAURIA OF NORTH AMERICA 



Family NOTHODONTIDAE Marsh. 



This family was established without diagnosis. 



Genus NOTHODON Marsh. 

 Am. Journ. Sc, vol. xx (3), 1899, p. 410. 



Type: A portion of the skull and some limb bones. Yale University Mus. 

 From New Mexico. 



Original description: "These reptiles may be readily distinguished by the 

 dentition. In each premaxillary there are two 



slender pointed teeth. In front of the maxillary ./Sfc M\ /"^"—n. 



there are one or two similar teeth, followed by a € f N f fi w 



number with narrow transverse crowns, resem- " '" I j [' j 



bling in form the premolars of some carnivorous a 6 ,<j 



mammals. These crowns, when unworn, have a 

 central cusp, and on each side a tubercle, some- 

 what like the premolars of the genus Cam's. In d , 

 the present species the first and last of the teeth 

 are smaller than the middle ones. The limbs 

 were short, the long bones had their extremities 

 covered with cartilage, but the carpals and tarsals 

 were well ossified. The centra were deeply con- 



d, ., * Fig. 7. — a,b, c , three teeth of X olhodon Itntus. 



the tail Was long. Y ale Univ. Mus. d, the same, a fragment of 



"The following measurements are taken from maxillary, x 1. 

 the type specimen of this species: 



M 



"Length of the maxillary bone . 0.065 



Space occupied by ten maxillary teeth 015 



Height of crown of second maxillary tooth 014 



Height of crown of third maxillary tooth 009 



Anteroposterior diameter 003 



Transverse diameter 008 



Anteroposterior diameter of the eighth tooth 005 



Transverse diameter 015 



"The present species was about 5 or 6 feet in length, and herbivorous in habit. 

 It was apparently slow in movement, and probably more or less aquatic." 



Nothodon lentus Marsh. 



The description of this species is embodied in that of the genus. 



Revised description: This family with its genus and species was founded on 

 extremely fragmentary material from New Mexico. The association of the teeth 

 with other parts of the skeleton is more than doubtful. The teeth closely resemble 

 those of Diadectes, but in view of the wide geographical separation from the locality 

 where Diadectes occurs and of the possible stratigraphical separation, it seems best 

 to retain the family provisionally until more is known of the skeleton. 



