TEIII) IJZAKDS OF TUE GENUS CNE.M IDoniOK US 109 



black gTouiuI color. With this biickground of indofiniteness it is at 

 once evident Avhy tiitM-c has been so luiicli confusion over tlu> form 

 ill later years. (liintliei- (Iss,-), p. L^^) wrote that '" iia\iiiii- some 

 doubt as to the propriety of including;- this anion**' the synonyms ol" 

 sci'-Ihwafus, 1 asked Professor von Martens for information; and 

 from his report it appears not only that the specimens of mexicanus 

 are identical with those in the British Museum which were collected 

 by Herr Forrer at Presidio, but also that Peters himself left a note 

 on the bottle containing the types that they were not distinct from 

 C. gularis (Baird and (iirard)." This identity with the Presidio 

 specimens of Sinaloa would seem to exclude the ])()ssibility of 

 nicricdniis bein<>: identical with jx rplc.ms. However, the southern 

 limit of the ^Mexican habitat of ixrph.rns in the west is still uncer- 

 tain. In 190G, Gadow described C. mexicanus typlca from spec- 

 imens from Oaxaca, listing the "types of G. mexicanus Peters" 

 under this heading. Oaxaca has already been mentioned as the home 

 of Gadow 's hocourtii. Moreover, Gadow said that " It is the irony 

 of fate that the three types of mexicanus are all immature and show 

 but little of the typical features * * * differing from those col- 

 lected b}' myself by decidedly larger scutes on the posterior side of 

 the forearm." This is interpreted to be an admission that young 

 specimens of Gadow's "subspecies " could not be distinguished from 

 each other, a conclusion forced u})on the writer after the examination 

 of a large series of Mexican specimens. Gadow also wrote (p. 360) 

 that ''A noteworthy character of these lizards is the com})lete ab- 

 sence of an}' j)ale spots, except those transitory faint sjjots in the 

 fields of young specimens. In this respect they differ conspicuously 

 from communis and its relations, with their numerous spots." Yet 

 both mexicanus and the spotted hocourtii of the communis group 

 were reported from Oaxaca. It has alread}^ been shown that the 

 spotted tjiJe may give rise to a cross-barred phase. In these spotted 

 and cross-barred forms of Oaxaca there is apparently' no difference 

 in size, in scutellation, or in color pattern of the young, and in old 

 adults of both the pattern fades anteriorly to a greater extent than 

 posteriorly. Because of this and because of the fact that both cross- 

 barred and spotted |)liases appear in (juJaris and pcvplcxus as a 

 frequent variation in widely separated regions, mexicanus and 

 " fypica " are considered as identical with gulari.s. 



CneniidopJiorus angusticeps from Yucatan, insutiicientlv tliag- 

 nosecl from •• communis " in the original description by Cope (1877, 

 p. 95) is apparently nothing but a synoinnn of gularis. It is not 

 unusual that the stripes " send off lateral processes and give the 

 ground color a very broken cliaracter." An examination of the 

 co-types shows that they have a patch of blue-black ventrally and 

 that they 2)ossess the usual four supraoculars of gularis. 



