1903.] NATURAL SCIENCES OF PHILADELPHIA. 545 



C. collaris from Seymour, Texas. In this series I find individuals with 

 a single row of interorbitals, and those with them partly divided, to 

 be each about two-fifths of the whole number, and those with a double 

 row about one-fifth. In association with these differences I do not find 

 any constant changes in the size of the supraoculars, in length of snout 

 or breadth of head. The last two proportions vary with age, old exam- 

 ples having much broader heads. These Seymour specimens are about 

 half-grown and were all collected together. 



The chief character of haileyi we thus find far outside of the region 

 assigned to it, in company with undoubted collaris and intermediates. 

 Two Crotaphytus in the Academy's collection, taken by Rehn and 

 Viereck in 1902, at Dry Canon, New Mexico, and assigned by Mr. Stone^ 

 to C. c. haileyi are like the Pecos and Seymour examples with double 

 interorbitals. If these specimens are haileyi, it occurs promiscuously 

 among collaris; if they are not haileyi, then the chief character of that 

 species occurs as a meaningless variation in collaris, leaving the former 

 species to stand upon slight and indefinable differences which vary 

 with age. In either case, the foundations of haileyi are not strength- 

 ened by their appearance. 



Crotaphytus wislizeni B. & G. 



Femoral pores in two specimens 18-22. Length of ? 324 mm. 

 (tail 208). This specimen in June has on the sides vertical bands and 

 spots of vermilion, which extend on the upper surface of the fore and 

 hind limbs and the under side of the tail. The pale cross-bands have 

 entirely disappeared from the body, but are distinct on another speci- 

 men 305 mm. long. 



Holbrookia maculata Giranl. 



Five specimens belonging to the form considered by Cope to be 

 H. m. maculata. Femoral pores in most cases 11 or 13; maximum 13, 

 minimum 9. 

 Holbrookia texana (Trosch.). 



Femoral pores usually 14-15; maximum in nineteen specimens 16, 

 minimum 12; very inconspicuous in females. The hind leg may fall 

 short of the eye or reach to the end of the snout. A cJ^ in June, doubt- 

 less in full breeding color, is very striking, there being much orange on 

 the shoulders, including the upper back, and on the forearms. The 

 hinder part of the back and sides and upper surface of the hind legs are 

 bright green, becoming yellowish on the tail. The jet-black lateral 

 crescents are set in a patch of rich blue which does not meet its fellow 



Proc. Acad, of Nat. Set., 1903. p. 30. 

 35 



