81. No fold of skin across the throat, or with only slight indications of one; 



scales of back uniformly large and each ending in a spine posteriorly 



82. 



With a fold or folds of skin across the throat; larger, spiny scales may or 



may not be present on the back in lengthwise rows 101. 



82. With a row of tiny scales extending about halfway back along the row 



of supraoculars, on the side away from the eye 83. 



With a row of tiny scales completely bordering the supraoculars, on 



the side away from the eye 85. 



83. Scales of back each deeply notched on each side of spiny tip; with a dark 



blotch on shoulder, but no distinct collar; Cal. 



Sceloporus orcutti Stejneger Orcutt's Spiny Swift 

 Scales of back not each deeply notched on each side of spiny tip; with a 

 dark "collar" on neck, which may be broken above 84. 



84. Legs dark barred; scales of back fully keeled; N. M. and Ariz. 



Sceloporus clar\ii clar\ii (B. & G.) Clark's Spiny Swift 

 Legs not dark barred; scales of back keeled about halfway from tips; 

 Utah to Ariz, and Cal. 



Sceloporus magister Hallowell Greater Spiny Swift 



85. With indications of a gular fold on each shoulder; with small, granular 



scales on the sides; Texas 86. 



No indications of a gular fold; with larger, overlapping scales on the 



sides 87. 



86. Tail dark barred above; W. Texas 



Sceloporus merriami merriami (Stejneger) Merriam's Canyon 



Swift 

 Tail ringed; Chisos Mts., Texas 



Sceloporus merriami annulatus Smith Merriam's Ring'tailed 



Swift 



87. With a dark, light-bordered band or "collar"' across back of neck 88. 

 Not so 90. 



88. Dark "collar" usually broken in the middle of the back of the neck; 



supraoculars (large scales covering the region of the eyeball) in one 

 row, bordered on each side by smaller scales; Ariz, and N. M. 

 Sceloporus jarrovn Cope Yarrow's Swift 

 Dark collar complete across back of neck; supraoculars at least partly 

 double, bordered on each side by smaller scales 89. 



89. Usually with only one or two supraoculars double; general color bluish; 



Texas 



Sceloporus cyanogenys (Cope) Blue Collared Swift 

 Supraoculars usually in two fairly complete rows above each eye; gen' 

 eral color reddish; N. M. and Texas 



Sceloporus poinsettii B. & G. Red Collared Swift 



90. Scales on sides in horizontal series; usually with a light hne lengthwise on 



each side of back passing through the center of a single row of scales; 

 belly unmarked; one color phase is plain brown above; Ariz. 

 Sceloporus scalaris slevini Smith Mountain Swift 



376 



