CROCODILIANS, LIZARDS, AND SNAKES. 377 



round bhickisb-blue spot on each side the throat. This subspecies is 

 about the size of the S. u. consobrinus, but it rather resembles in color 

 the >S'. u. undulatns. It has only one occipital plate on each side, and the 

 arrangement of the supraocular plates is unlike that of any other sj^ecies. 

 Posteriorly the large transverse supraoculars are only separated from 

 the superciliaries by a single series of lanceolate scales like the super- 

 ciliaries. For their anterior half they are separated from this lanceo- 

 late series by two or three wider scales, forming a single row. There 

 are two to three rows of rounded scales in the same position in the *S^. u. 

 vndiilattis and S. u. consobriuKS. In the former subspecies from both 

 coasts there are two rows of scales between the suborbital plate and 

 the suj)erior labials. In the 8. u. tristichus there is only one such row, 

 which consists of lanceolate scales. Thus this form ditfers from the S. 

 tmdulafvs in a direction the opposite of the S. Mseriatiis. 



As to colorations, there are eight cross bands between the groin and 

 axilla, while in the 8. u. undulatus from both coasts there are five or six. 



Measurements. — Total length, 132 mm.; length to vent, 59 ram.; 

 length to axilla (axial), 27 mm.; length to ear (a"ial), 14 mm.; length 

 of fore leg, 24 mm.; length of fore foot, 11 mm.; length of hind leg, 

 37 mm. ; length of hind foot, 18 mm. 



This form diilers considerably in appearance from the 8. undulatus, 

 but as it is represented by but one specimen it may turn out to be a 

 variety of that widely distributed species. 



Sceloporus imdulatus tristichus Cope. 



SCELOPORUS UNDULATUS CONSOBRINUS Baird and Girard. 



Sceloporus cousohrinus Baikd and Giraho, Marcy's Report oii Red River, Reptiles, 

 1853, p. 237, pi. X, pp. 5-12.— Baird,!;. S. Pac. R. R. Surveys, Whipple's Report, 

 Reptilia, 1859, p. 5.— Copk, Bull.U. S. Nat. Mus., No. 17, 1880, p. 17.— Stej- 

 NEGER, N. Amer. Fauna, No. 3, 1890, p. 111. 



Sceloporus garmanl Boulenger, Proe. Zool. See. Loud., 1882, p. 761, pi. L^■^. 



Supraorbital region with one cresentic series of six large transverse 

 plates, embracing a much smaller one (of four or five) in its concavity, 

 the whole bordered by a complete row internally and externally. Two 

 central single plates, with a third more anterior, surrounded by five 

 others, tlie plates all smooth. Occipital large, with two or three plates 

 on each side, free portion of longest hind toe reaching to middle of 

 occipital plate. Scales of back, rump, and sides of body not conspicu- 

 ously diflerent in size, those of tail alone larger. Dorsal scales angu- 

 lar, strongly carinated, mucronate with free spines and with lateral 



