TEIID LIZARDS OF THE GENUS CNEMIDOPHOIlUS 161 



sioii of yix stripes instead of four * * ''' alters this form to pcr- 

 2)lex'us rather than to ■laelanosteflni.'^.'' The above statements seem 

 to require ehiboration and explanation. Tlie types of acthlops are 

 in very poor condition and the pattern is faded and darkened, except 

 in one specimen (U.S.X.M. Xo. 64241). The appearance of a black- 

 ish suffusion dorsally, especially over the scapular region, is by no 

 means rare in tessellatus^ particularly in some parts of Arizona. 

 AYhen the black suffusion covers the entire lizard, however, one may 

 suspect artificial staining or darkening, perhaps, since melanism usu- 

 ally progresses with the addition of black pigment to one part and 

 the loss or subtraction of that pigment from another. Thus, in 

 most of the Arizonan specimens which have a deep black suffusion 

 over the scapular region, the posterior part of the back is usually 

 practically devoid of black pigment, having much brownish as a 

 rule. In regard to the cotypes of aethwjJS, it is also found that the 

 femora are both spotted and reticulated with white, so the pattern 

 of the hind legs is not particularly different from that usually found 

 in tessellatus. The presence of six stripes instead of four is not un- 

 usual. It has already been pointed out that a specimen from Thomp- 

 son, Utah (C.A.S. No. 38163), has been found Avith as high as eleven 

 stripes and that an increase from the usual four stripes is not at all 

 uncommon in certain areas. Therefore, the presence of six stripes 

 scarcely indicates relationship witli perplexus^ which differs de- 

 cidedly from the types of aethiops in tliat the ventral parts are white 

 instead of black. 



In the original description of aethiops it was also stated that 

 "A form very much like this has been named martyris by Stejneger. 

 The two known specimens differ from melanostethus in their smaller 

 size and in the extension of the black over the entire inferior surface. 

 It is doubtful whether it can be regarded as a subspecies." It may 

 be remarked that martyris is much closer to the specimens from 

 Parras and Lerdo that have been discussed as variolosus than to 

 the geographicall}^ adjacent aethiops, since it has lost practically all 

 indications of longitudinal arrangement in the dorsal markings and 

 the markings themselves are extremely fine. It will be remembered 

 that aethiops has, characteristically, six stripes. With the accumu- 

 lation of additional specimens it has been found that the extension 

 of black over the entire ventral surface occurs in certain " Qiielanoste- 

 thus " from the United States, so this point is not important here. 

 Therefore, Gadow's listing of aethiops as a synonym of martypis 

 (1906, p. 373) was evidently a misconception. 



Because of the failure of the diagnosis of aethiops and because 

 of its obvious similarity to northern specimens of tessellatus, the 

 name is here placed as a synonym of the latter. This agrees with 

 the conclusion reached by Van Denburgh (1922, p. 529). 



