108 BULLETIN^ 15 4, UNITED STATES NATIOiSTAL MUSEUM 



the most abberant clans of communis tending toward 'bocourti and 

 mexicaiius, or as abberant immufahilis and ffutfatus, which assume 

 characters ty})ical of communis. Such are the C. communis aus- 

 tralis.'''' Just why ti'aiisition from guttatus^ the hxrge, intensified 

 deppii with three supraoculars and a distinctive coloration, to copei 

 or other members of the gularis stock, should be mentioned here 

 is not apparent. Superficially these forms may resemble each other 

 by assuming a spotted garb, but in guttatus the spots are con- 

 fined to the dorsal region and in gularis the continuous lines of the 

 sides are usually the first to break into spots or cross-bars. The 

 latter do not appear in guttatus. Since austo'alis does not occupy a 

 distinctive range, and an examination of part of the cotypes shows 

 them to be nothing but gularis, the form is not given recognition 

 here. 



The original descrii)tion of Gadow's C. communis occideritalis is 

 even more indefinite than his description of australis. Since a diag- 

 nosis is not given the following characteristics are taken from the 

 key (p. 328): "Stripes dissolved into rows of pale spots; many 

 longitudinal rows of pale and round spots, Mexico; forearm with 

 scutes or polygones; humerals and femorals 5-7; chest and abdomen 

 pale." An examination of a large series of cotypes in the collec- 

 tion of the Field Museum of Natural History shows that part of 

 them are perplexus, although the most are gularis. It is surprising 

 that the dissolution of the stripes into rows of spots should be em- 

 phasized as a key character, since all of the young cotypes are 

 distinctly striped, occasionally even being entirely unspotted. The 

 presence of scutes or polygones on the postantebrachium is not dis- 

 tinctive and the number of humerals and femorals is highly variable, 

 the range given here being typical i-athcr than differentiative. Tlie 

 chest and abdomen are pale in only part of the cotypes, those aj)- 

 ]3roaching pcrpJexus., and in some the ventral suffusion is blue-black 

 as is typical of gularis through the typical part of its range. A com- 

 parison of some of the smaller cotypes of occidentalis with the 

 cotypes of meehl shows them to be identical, and the larger speci- 

 mens are, as a rule, the same as one of the phases described from 

 Chihuahua by Cope (1886), although occasionally much spotted, 

 unstripecl specimens which are without cross-bars, are seen. Thus, 

 for apparent reasons, occidentalis can not be retained as a distinct 

 entity. 



IV. The "mexicanus" group, like the one just discussed, was 

 largely developed by Gadow (1906). It consists of the following 

 described forms: Mexicanus, angiisticeps., typff^-, '"^rid halsas. 



CnemidopJtorus mexicanus was described by Peters (1869Z>, p. 62) 

 with no other locality than " ]\Iexico." It was said to be a close 

 relative of sexlineatus, having six light stripes and an unspotted, 



