TEIID LIZAEDS OF THE GENUS CNEMIDOPHOKUS 121 



Gularis is largeW intermediate between sexlineatus and perplexus, 

 differing from sexlineatus in the same way as perjjUexus differs from 

 sexlineatus (by the much hiraer maximum size, frequent appearance 

 of spots or crossbars on the sides, and the usual presence of enlarged 

 scutes or polygones on the posterior surface of the forearm), and 

 differing from perphwiu^ in the same wa}' that sexlineatus differs 

 from perflexus (by the presence of a widened, yellowish, middorsal 

 streak and a wider dorsal field). Yet, in addition, gularis differs 

 from both in the presence of a bluish ventral suffusion Avhich offers 

 an approach to the southern deppii group with wdiich it was pre- 

 sumably linked at one time through a common ancestral population. 

 This is held to support the theory of the derivation of sexlineatus 

 and perplexus from a central gularis stock rather than the deriva- 

 tion of gularis from one of these, particularly from sexlineatus. At 

 the line of intergradation between gularis and perplexus the bluish 

 N'cntral suffusion and the yellowish middorsal streak of gularis is 

 lost and leaves the unifoiiu ground color, above and below, which is 

 so characteristic of perplexnx. Here also tlie lines are modified, the 

 tliird pair from tlie bottom on eacli side migrating tow^ard the center 

 of the back to jiroduce a predominately G-lined form which has a 

 narrow middorsal interspace, or a 7-lined form with a distinct, in- 

 stead of a diffuse, middorsal stripe — such as the modern perplexus. 

 While perplexus is merely a color variety of gularis^ it is distinct 

 outside of the area of intergradation, and as such presents a funda- 

 mental evolutionary divergence from gularis. 



Recently, Strecker (1929«, p. 6) has written, while admitting 

 that color characteristics are often misleading, that " the same ob- 

 servation might be made for the number of scale rows and femoral 

 pores. If sexlineatus and gularis are varieties of the same species, 

 there is in this section of Texas (Wilbarger County) a marked dif- 

 ference between them in size, life coloration, and to a lesser degree, 

 in their habits and environments." It may be remarked here that 

 Strecker's observations on color characteristics and the number of 

 femoral pores are in exact accordance Avith those of the w'riter. Also, 

 the number of longitudinal ventral scale rows is eight in most 

 species of Cneimdophorus^ and in addition the number of ventral 

 rows and the number of dorsal rows are not used in classification 

 here. Several detailed accounts of local differences between sex- 

 lineotms and gularis, or between gularis and perplexus as well, in 

 regions wdiere they occur together as presumably distinct and non- 

 intergrading units are much to be desired. The writer believes that 

 such accounts will call attenti(m to "local phases," to change in 

 habitat due to age, to a definite response to the influence of environ- 

 ments, and, very likely, even to confusing intergradation itself. 

 2.306—31 9 



