326 DR. n. GADOW ON EVOLUTION [Mar. 20, 



priority of name ; genetically it is the teniiinus of a series which 

 begins with the entirely striped race : 



II. C. immutabilis of Cope. By irony of fate this is the proper 

 name of one of the most variable of lizards. It is what I called 

 C. (jnttatus var. striata in Proc. U.S. 1903. Cope's types came 

 from " West of Tehnantepec." 



The characteristic feature of this brighter-coloured race is the 

 6 to 8 continuous white stripes on a mther uniform and dark 

 ground. 



Such typically striped specimens are now known from San 

 Mateo del Mar, Salina Cruz, Tequesixtlan, Cocoyul and Pacific 

 Coast east of Acapulco, Miahuichan, and southern slope of Los 

 Cajones. In general terms : the coast region of the States of 

 Oaxaca and Guerrero ; how much furthei- west along the Pacific 

 Coast I'emains at present unknown. 



I have found it exceedingly difficult to keep free from bias 

 whilst assorting these very variable lizards according to the 

 prevalence of either stripes or spots, and still more difficult cleai-ly 

 to pronounce upon the physical features of their localities. How- 

 ever, I can affii-m the result that in the small open localities the 

 striped lizards prevail, almost to the exclusion of more than two 

 I'ows of spots ; while in places with many shrubs, much underwood, 

 absence of large grassy and sandy patches, the sjiotted forms 

 prevail, in the more typical bush forests of the Atlantic side 

 almost to the exclusion of stripes. 



Open localities, either strips near the sea-shore, sandy beds 

 of frequently dry rivers, grassy stretches with scanty trees, and 

 nowhei'e covered during half the year with lank and dense 

 herbaceous gi'owth, were the collecting spots of Cocoyul, Salina 

 Cruz, San Mateo, Tequesixtlan, San Domingo de Guzman ; also 

 Miahuichan, a spot on higher ground and just above the luxurious 

 tropical growth of forests ; likewise the open giassy slopes near 

 Rincon at the southern slope of Los Cajones, amongst scanty 

 pine-forests. 



Much tangled undei'wood, broken terrain, well wooded ravines, 

 or meadows with tall grass and herl)S, or rivers fringed with masses 

 of shrubs, were the features of Tieriu Coloi'ada, Ayutla, and San 

 Luis Allende ; those very spots which yielded the most inter- 

 mediate specimens. 



In the Atlantic Tierra caliente, with its decidedly denser 

 vegetation, with fewer deciduous trees, and much gi'eatei- annual 

 rainful, the typical C. guttatns alone is found, for instance at Agua 

 fria, San Juan Evangelista, La Antigua (V.C). Of course there 

 are many and lai'ge Savannahs in the lower coast- districts of the 

 State of Vera Cruz, and it would be interesting to ascertain whether 

 any large Cnemidojyhori occur in the open Savannah, and not only 

 in the vicinity of the tyjHcal clusters or patches of trees. Pei sonally 

 I have but little expei-ience of these parts. All I can affirm is 

 that I have seen no CvemidojyJwrus near Tetela, only C. guttatns 

 at Agua fria, the same form and 0. deppei at San Junn Evangelista 



