F. A. Lucas — Contributions to Paleontology. 399 



Art. XXXIX. — Contributions to Paleontology ; by F. A. 



Lucas. 



[Published with the permission of the Secretary of the Smithsonian Institution.] 



1. A New Crocodile from the Trias of Southern Utah. 



The following genus and species is based upon the imper- 

 fect anterior portion of the lower mandible of a crocodile com- 

 parable in size with Tomistoma among living and Thoraco- 

 saurus among extinct species. The mandibular symphysis is 

 long, though less than in Tomistoma, and includes a consider- 

 able portion of the splenial. The teeth are very close to one 

 another, being separated by an extremely thin partition of bone, 

 and the tooth row lies in a broad shallow groove. The teeth 

 are set obliquely, raking decidedly outwards, and they are com- 

 pressed from before backward, the antero-posterior diameter 

 being slightly less than the transverse. The two anterior teeth 

 are round in section and vastly larger than the others, the end 

 of the jaw being expanded for their accommodation. The 

 surface of the bone is somewhat pitted, there is a deep narrow 

 groove along the side of the jaw and there is no notch for the 

 upper canines and no depressions for the reception of any of 

 the upper teeth. The genus is characterized by the antero- 

 posterior compression of the teeth, their closeness to one 

 another, and by the great size of the two anterior teeth. The 

 name Heterodontosuchus ganei is proposed for the genus and 

 species, the specific name being given in honor of the dis- 

 coverer Mr. H. S. Gane, by whom it was transmitted to Mr. 

 Whitman Cross of the U. S. Geological Survey. The speci- 

 men is from Clay Hill, Southern Utah, and is from the Trias 

 at the top of No. 10 of the section given by J. S. Newberry 

 on page 99 of the Keport of the Macomb Expedition. The 

 horizon is said by Mr. Cross to be the same as that from which 

 teeth of a crocodile — probably a Belodon — and of a species of 

 Palceoctonus were obtained by him in the Telluride, Rico, and 

 La Plata Quadrangle of southwestern Colorado. Type No. 

 4136, U. S. Natl. Museum. 



2. A New Species of Dinictis (D. major). 



Among some specimens collected by Mr. N. H. Darton, of 

 the U. S. Geological Survey, in 1897 is a species of Dinictis 

 which proves to be new and the largest species of the genus 

 yet discovered. The distinctive characters are the size of the 

 animal, the feeble development of the mandibular flange for 

 the protection of the upper canine, the robust character of the 



