9. HOLBROOKIA 175 



mm. long, while four 59 mm. males from the Santa Ritas 

 have tails 45, 46, 46, and 49 mm. in length. I am therefore 

 forced to refer all these specimens to the same subspecies. 

 For this subspecies I have followed most recent authors in 

 using the name //. maculata approximajis, although the type 

 is said to have been collected on the "Lower Rio Grande." 

 Although I have followed Barbour and Schmidt in describ- 

 ing the specimens from Guaymas, Sonora, as H. elegans, 

 they seem to me to be very doubtfully distinct from the 

 present subspecies. 



Habits. — This species we found always on the ground 

 and usually out on the open desert, while H. texana frequents 

 canyons and hillsides, and usually was seen on the tops of 

 large stones or boulders. 



29. Holbrookia elegans Bocourt 

 Mexican Earless Lizard 



Holbroohui elegans Bocourt, Miss. Sci. Mex., Rept., 1874, p. 16+, pi. 

 XVII bis., fig. 8, 8a (type locility, Mazatlan, Mexico) ; Bou- 

 LENCER, Cat. Lizards Brit. Mus., Vol. II, 1885, p. 209; Barbour, 

 Proc. New England Zool. Club, Vol. VII, 1921, p. 113; Schmidt, 

 Amer. Mus. Novitates, No. 22, 1921, p. 2 (part). 



Holbrookia trofviqna Boulenger, Cat. Liz. Brit. Mus., Vol. II, 1885, 

 p. 208; GiJNTHER, Biol. Centrali-Amer., Rept., 1890, p. 60. 



Holbrookia 77iaculata afproximans Van Denburch, Proc. Acad. Nat. Sci. 

 Phila., 1897, p. 461 (part). 



Holbrookia thermofhila Barbour, Proc. New Eng. Zool. Club, Vol. VII, 

 1921, p. 79 (type locality, Guaymas, Sonora, Mexico). 



Descriftion. — Head rather short and low. Nostrils 

 large, opening on upper surface of snout. Supraocular 

 regions covered with small plates or granules, and separated 

 from each other by one or two rows of slightly larger 

 plates. Upper head-plates, except interparietal, small and 



