49. scELOPORUS. 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. dugesti, 
Mexico. 
2. Sceloporus serrifer. 
Sceloporus serrifer, Cope, Proc. Ac. Philad. 1866, p. 124, and Proc. 
Am, Philos. Soc, 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 shiclded 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. millim, 
Total length ...... 164 Fore limb ........ 38 
Head gee sersee ats os 19 Hind limb ........ 52 
Width of head 18 Pais saree Bisset why th 92 
Body ascenw se tees 53 
Yucatan. 
a &. Mexico, M. Sallé [C.]. 
3. Sceloporus acanthinus. 
Sceloporus acanthinus, Bocourt, Miss. Sc. Mex., Rept. p. 180, pl. xviii. 
fig. 10, and pl. xix. fig. 4; Cope, Proc. Am, Phil. Soc, xxii. 1885, 
p. 896. 
Head-shields smooth ; a series of four or five very large transverse 
supraoculars, bordered internally by an incomplete series of very 
small scales ; two canthal scales ; occipital as long as broad, much 
larger than the parietals; anterior border of ear with a strong 
