Measurements. 

 Length of entire dentary bone .... 

 Depth at posterior border of symphysis . 



" " last tooth 



" to internal groove ..... 



" " " foramen .... 



Length of crown of second tooth 



( antero-posterior 

 Diameter of second tooth at base { . 



( transverse . 



Length of crown of twelfth tooth 



( antero-posterior 

 Diameter at base of twelfth tooth < tl . QT , 0T7OI ._. 



^ tlaliovclati 



Length of crown of superior Pcanine 

 Antero-posterior diameter of do. 



M. 



.525 

 .110 

 .192 

 .060 

 .074 

 .029 

 .013 

 .018 

 .043 

 .025 

 .017 

 .062 

 .028 



As compared with the Lselaps aquilunguis, of which a portion 

 of the dentary bone is known, this species differs in the greater 

 diameter of its inferior border anteriorly, in the presence of the 

 internal groove, in the greater elevation of the external alveolar 

 wall, and, if the character be constant, in the greater robustness 

 of the form of the dental crowns. The individual here described 

 is rather larger than the type of L. aquilunguis, but it is probable 

 that the species were not very different in dimensions. 



Laelaps hazenianus, sp. nov. 



Seven teeth from different localities present constant charac- 

 ters which readily distinguish them from all other species of the 

 genus. Their size is less than those of the two species above 

 mentioned, and is greater than in the species enumerated below. 



The crowns are short and robust, and are abruptly terminated 

 by the strong recurvature of the anterior cutting edge. The apex 

 has, therefore, a more posterior direction than in the L. incrassa- 

 tus, while the anterior cutting edge is shorter. The latter is short- 

 ened below also, not extending to the base of the enamel, but ter- 

 minating in a short lateral curvature. At the base, therefore, the 

 anterior border is rounded, while the posterior is acute. The 

 denticulations are of medium size, measuring M. .00033. 



Measurements. m. 



Length of crown 014 



( antero-posterior 011 



Diameter of crown < . nn ~ 



( transverse 007 



Both sides are convex, but not equally so, and the surface is 

 smooth, and without facets. 





