This saurian is dedicated to General Hazen, now in command at 

 Fort Buford, Dakota, as a token of respect for his qualities as a 

 man and his services in the interest of science. 



Lselaps lsevifrons, sp. nov. 



A tooth half the size of those referred to the L. hazenianus, and 

 exceeding by a little the largest of those of L. explanatus, pre- 

 sents such characters as induce me to believe that it belongs to a 

 species distinct from either. It is of the elongate acuminate form 

 of some of those referred to the L. incrassatus, and both sides are 

 convex, but not equally so. A shallowly concave plane occupies 

 the middle of the more convex side. The posterior cutting edge 

 is denticulate to the base, but the anterior, though of the same 

 form as in the other species, and unworn, is absolutely smooth. 

 In this respect it differs from the other species, excepting L.fal- 

 culus. The denticulations are finer than those of any other spe- 

 cies, measuring M. .00020 ; in L. explanatus they measure M. 

 .00022. 



Measurements. m. 



Elevation of crown 015 



n ( antero-posterior 007 



Diameter of crow { transverse 004 



Lselaps explanatus, Cope, Proceedings Academy, October, 1876. 

 Lselaps falculus, Cope, loc. cit. 

 Lselaps cristatus, Cope, sp. nov. 



Another small species well distinguished by the form and 

 coarse denticulation of the teeth, approaching the genus Troodon. 



The crowns of the teeth are short, stout, compressed, and 

 curved. Both sides are convex, and neither is facetted. The 

 denticles are large, those of the posterior cutting edge the largest, 

 and measuring M. .0005. A characteristic feature is the full devel- 

 opment of the denticulate anterior cutting edge of the crown. 

 This extends to the base, becoming more prominent as it descends. 

 Surface smooth. 



Measurements. m. 



Elevation of crown 011 



_. c antero-posterior 006 



Diameter of crown \ . noo 



(transverse 003 



ZAPSALIS, Cope. 

 The teeth of this genus are intermediate in form between those 

 of Lselaps and Paronychodon. They have one flat and one con- 



