174 BULLETIN 15 4, UNITED STATES NATIONAL MUSEUM 



hiiicliiuni with small of sli<ihtly ('nlar<ie(l <irainiles; femorals 5-11; 

 tibials 2-5; femoral poiv.s 15-25. Tail clonpite, taperin^Li;; caudal 

 plates lar<^e, obli(iiu', and with rather stronj^ lonuitiidinal keels 

 laterally. 



Coloration hiuhly variable: throat, white to deep l)lack, spotted or 

 unspotted, Avith or without tiiier bai-s. ne\er suffused with red or 

 l)inkish; breast, white to deep black, spotted oi- unspotted, larely 

 with a li<^lit bluish suffusion, sometimes mottletl black and white; 

 abdomen sometimes Avhite in distinct contrast to a black chest, some- 

 times white like chest, and sometimes black like chest, spotted or 

 unspotted; under .surface of feet and tail not suffused with red or 

 ])inkish as in ruhidits, bnt white, slate, yellowish, brown, dnsky, or 

 l»lack; snbcau(hil daik spots present or absent; sides and dorsal 

 surface of tail usually with some daik inarkinas and I'eticulations. 

 OI' washed with a chocolate or bladi suffusion: femora unspotted, 

 I'eticulated, or spottetl, sometimes unicoloi-; sides never with com- 

 jdete strij)es, but with tessellations, crossbars, or spots; back often 

 with four more or less wavy or broken dorsal lines, but sometimes 

 as high as twelve are present ; dorsal pattern, thus, usually with at 

 least some indications of lono;itudinal arran<^ement ; or, with coarse 

 reticulations; ground color of back variable, light brown to black; 

 dark and light in i>attern shai'ply contrasted or not: in forms with 

 black throats and chests, often a black scapular .suffusion from 

 below. 



Variation. — There is much geographical yariation in the colora- 

 tion of tesseUatu.s. Specimens from the lower levels, particularly 

 from deserts, tend to become brownish above and black below, while 

 those from the higher, more mountainous districts tend to become 

 black above in ground color, and Avhite below. In the former phase 

 the dorsal pattern is poorly defined, but it is Avell defined in the latter. 

 The subject introduced here is amplified above in the systematic 

 notes, particularly on pages 154-157, and 166. 



The general scutellational and proportional features seem to be 

 everywhere relatively constant or relatively variable. This will be 

 evident from an examination of the tAvo tables presented liereAvith. 



The first table presents the measurements, proportions and number 

 of femoral pores of representative series of mainland specimens of 

 the tessellated lizard. The Arizonan specimens are from Maricopa 

 and Pima counties only and represent the " meianostethus'''' phase at 

 its place of maximum development. The Californian examples rep- 

 resent " stcjnegerl and mundus^'' and the Texas ones, " grahaimiP 

 It will be evident that the bodily proportions (which offer the only 

 real basis of comparison for specimens of all ages) as AA'ell as the 

 measurements and the numbers of femoral pores, shoAv little varia- 



