13. PHRYNOSOMA 371 



Remarks. Bell described A. douglassu^ in 1833, from 

 specimens collected on the banks of the Columbia River. 

 Since then similar lizards have been found as far east and 

 south as Wyoming, Arizona and Texas, and various names 

 have been applied to them. 



There still is much confusion and lack of definite knowl- 

 edge regarding the differential characters and the distribu- 

 tion of these short horned Phrynosomas of western North 

 America. Girard, who was the first to study this group, 

 proposed several names which later were used almost indis- 

 criminately by Cope and Yarrow in their various publica- 

 tions. 



The names Tapaya hernandesi and T. ornatisslma were 

 originally given by Girard to horned toads from New Mex- 

 ico. The latter was stated to have come from the moun- 

 tainous region. Stejneger, after examining the type speci- 

 mens in conjunction with speciments from Arizona, con- 

 cluded (1890) that there were two species in that state; the 

 one, found in the mountains and wooded plateau region, 

 agreed with the type of T. hernandesi in having all the head 

 spines larger and the occipitals more horizontal; the other 

 kind, from the Painted Desert and Desert of the Little 

 Colorado, was like the type of T. ornatissima, in which the 

 head spines were smaller and the occipitals more erect. 

 Because these differences were constant in his Series of 

 specimens, Dr. Stejneger regarded the two as distinct spe- 

 cies Phrynosoma hernandesi and Phrynosoma ornatissi- 

 mum. 



Dr. Stejneger (N. Amer. Fauna, No. 3, pp. 112-115), 

 stated "that the examination of a very extensive material 

 has convinced me of the necessity of recognizing at least 

 four different forms, each with a definite and distinct geo- 

 graphical distribution, viz, the typical Ph. douglasm ( 

 ^ygmaea) from Oregon and Washington; Ph. hernandesi 



