49. scELOPORtrs. 221 



pores. A black scapular spot -which, sends a narrow black line 

 upwards and backwards, which sometimes meets its fellow of the 

 opposite side, but generally fails to do so by one or two scales. 



About the size of S. dugcsii. 



Mexico. 



2. Sceloporus serrifer. 



Sceloporus serrifer, Cope, Proc. Ac. Philad. 18(3G, p. 124, and Proc. 

 Am. Philos. Hoc. xxii. 1885^ p. 395. 



Head- shields smooth ; a series of five very large transversely 

 dilated supraoculars, bordered internally by an incomplete series of 

 minute scales ; two canthal scales ; occipital nearly as long as broad, 

 much larger than the parietals ; anterior border of ear with a 

 denticulation formed by six pointed scales, which are scarcely as 

 large as those preceding. Dorsal scales larger than ventrals, strongly 

 keeled, and ending in a long spine ; on the posterior part of the 

 back the scales slightly converge towards the vertebral line ; thirty- 

 five scales between the occipital shield and the base of the tail ; ten 

 scales correspond to the length of the shielded part of the head ; 

 lateral scales keeled, directed obliquely upwards and backwards, 

 nearly as large as dorsals ; ventrals smooth, distinctly bicuspid ; 

 forty- two scales round the middle of the body. The adpressed hind 

 limb reaches between the ear and the orbit ; tibia as long as the 

 shielded part of the head ; the distance between the base of the 

 fifth toe and the extremity of the fourth equals the distance between 

 the nostril and the arm. Ten or eleven (nine) femoral pores. 

 Caudal scales like the dorsals. Olive above, brown-spotted ; a dark 

 brown collar, interrupted in the middle. " Throat and sides of male 

 blue, the latter broadly black -bordered behind and medially." 



millim. milliin. 



Total length 164 Fore limb 38 



Head 19 Eind limb 52 



Width of head .... 18 Tail 92 



Body 53 



Yucatan, 



a. 2 ■ Mexico. M. Sall(5 [C.]. 



3. Sceloporus acanthinus. 



Sceloporus acauthiuus, Pocourf,Miss. Sc.Mex.,Rept. p. 180, pi. xviii. 

 tig. 10, and pi. xix. tig. 4; Cope, Proc. Am. PJnl. Soc. xxii. 1885, 

 p. 39G. 



Head-shields smooth ; a scries of four or five very large transverse 

 supraoculars, bordered internally by an incomplete series of very 

 small scales ; two canthal scales ; occijiital as long as broad, much 

 larger than the parietals ; anterior border of ear with a stron<> 



