30 PROCEEDINGS OF THE ACADEMY OF [1883. 



mesosternum is cruciform in Lepidophyma and Xantusia. I have 

 not been able to examine Griconaura as to these points. In my 

 paper first mentioned, I stated that these genera have distinct 

 parietal bones. I think that they should, on this account, be 

 distinguished from the Lacertidse^ where they are coossified. 

 Whether they are distinct or united in the Ecpleopidse, I do not 

 know, but the absence of e^-elids will separate the group from 

 that family. I use for it the name first given by Baird,^ Xantu- 

 sidse^ and characterize the three genera as follows : — 



I. A large interfrontonasal plate ; frontoparietals 



meeting on the middle line. 



Superciliar^'^ scales none ; pupil round ; Lejndophyma. 



Superciliary scales present ; pupil vertical ; Xantusia. 



II. Two interfrontonasals ; frontoparietals separated 



by interparietal. 



Superciliary scales; Cincosaura. 



All of these genera have femoral pores, and an exposed mem- 

 branum tympani. 



The species which has given occasion for the above discussion 

 is the second one of the genus. It is several times as large as 

 the type X. vigilis Baird, and has a different coloration. The 

 digits are shorter. 



The scales of the dorsal and lateral regions are rather coarsely 

 and nniforml}^ granular. The abdominal scales are quadrate, and 

 are in sixteen longitudinal and thirt3''-two transverse rows. The 

 preanal scales ai'e in three transverse rows, the anterior two of 

 four scales, with the median pair in both much enlarged, and the 

 posterior row of six scales. Scales of the gular region flat and 

 hexagonal, one row on the gular fold a little larger, and equal to 

 the anterior gulars. Scales of the anterior aspects of the fore-leg 

 and femur larger than the others ; those of the tibia small, and 

 those of the posterior face of the femur still smaller. Scales 

 of the tail in whorls of equal width. The scales of equal size, 

 and all convex in cross-section but not keeled. None of the 

 scales of the body or limbs keeled. 



The nostril is situated in a small scute at the junction of the 

 sutures which separate the internasal, rostral, first labial, and first 



^ Proceedings Academy Philadelphia, 1858, December. 



