Cope.j ^dli |- Dec- 2i, 



Pal^eosatjrus fraserianus sp. nov. 



But few remains indicate this species. It is established primarily on a 

 tooth, which presents the characters of Palwosaurus cylindrodon. It has 

 opposite denticulate cutting edges, an anterior and posterior, of which the 

 latter extends to the base of the crown, and the anterior but half way from 

 the apex. The posterior is denticulate throughout, Avhile denticulation is 

 visible on the anterior edge for but one-third the distance from the apex. 

 The posterior edge is more compressed. The surface of the cementum is 

 obsoletely finely linear ridged, and there are no sulci or other sculpture. 

 The crown is regularly and gently curved backwards. 



Measurements. M. 



Length of the crown 0200 



Antero-posterior diameter of crown at base 0065 



This saurian is dedicated to my friend, Persifor Frazer, Jr., in charge of 

 one of the districts into which the State of Pennsylvania is divided for the 

 conduct of the second geological survey. This district embraces the Tri- 

 assic region, which has been extensively and ably investigated by Prof. 

 Frazer. 



SuCHOPRION ATJLACODUS Cope. 



Paloioctonus aulacodus Cope, Paleontological Bulletin, No. 26, p. 184. 



Several additional teeth of this species show that the tooth from which I 

 first determined it is one of the flattest of the series, and that those from 

 other positions in the jaws, instead of being flatter as in Palwoctonus, are 

 narrower, and of the usual form of those of Suchoprion. 



This saurian possesses teeth of the size of the average of those of the S. 

 cyphodon, and which are like them, well compressed in the antero-poste- 

 rior direction. The surface is therefore very convex between the cutting 

 edges, especially on the external face, and the transverse diameter at the 

 base of the crown exceeds the antero-posterior. The cutting edges only 

 extend half way from the apex, and are but little denticulated. The sur- 

 face of the cementum is minutely and sharply linearly sculptured. It is 

 in addition, thrown into coarse continuous grooves on the basal two-thirds 

 of the crown, excepting for a short distance on the inner side of each cut- 

 ting edge. There are seven grooves on the inner face, and eighteen on the 

 outer face. On the latter the minute sculpture is least distinct. 



Measurements. M. 

 Length of crown 0260 



Diameter of base of crown | foreand aft 01 f° 



I transverse 0115 



The short slightly denticulate cutting edges and the strongly grooved 

 surface distinguish the anterior teeth of this species at once from the 8. 

 cyphodon. Several specimens have been found by Mr. "Wheatley. 





