TEIID LIZARDS OF THE GENUS CNEMIDOPHORUS 173 



Neither of these speciiueiis agrees Avith the description of the t3^pe 

 in dorsal coloration, showing none of the alternating of the spots in 

 the dorsal rows. Van Denbiirgh was doubtful of the distinctness 

 of this species from inihidus. Of the specimens before me the dorsal 

 coloration of one resembles stejnegeri while that of the other re- 

 sembles I'uhhlus. The gular region of the former shows less of the 

 black markings characteristic of dejiieyefl^ while the latter has the 

 black throat found in specimens of ruhklun from Magdalena Island. 

 More material and future study may prove this species to be an inter- 

 grade between ruhkhis and stejnegeri.''^ 



An examination of the types discussed by Sclimidt and the two 

 additional specimens mentioned by Slevin indicates that all are 

 tesselhffus, for none of them have reddish or pink tails (the most 

 outstanding characteristic of rii^hidus). The doi'sal color pattern is 

 in most cases tA^pical, but in the two specimens mentioned in the 

 above discussion, there is a decided tendenc}^ to approach that of 

 I'uhidus^ just as one might expect from their geographical position. 

 Therefore, more perfect intergrades between r-ubidns and tessellatus 

 may be expected from a point south of Ballenas Bay when more 

 specimens are collected. 



Diagnosis. — The desert whiptail may be distinguished from other 

 Cnemidophori as folloAvs: Supraoculars normally 4; frontoparietal 

 plates normally 2 ; postantebrachials small or only slightly enlarged, 

 never scutelike; under surfaces of tail and feet Avithout red or 

 pinkish; ventral suffusion or spotting, if present, blackish and not 

 bluish as in gidaris; sides of body never completely striped; lateral 

 crossbars, spots, or reticulations present ; dorsal pattern usually with 

 at least some indications of longitudinal arrangement, if without 

 these, a network of rather coarse reticulations present. 



This subspecies is most apt to be confused with martyris and cwriU'S^ 

 from which it may be separated at times only Avitli difficulty. As 

 a rule it is larger than these forms and it always has relatively 

 coarser dorsal markings. 



Description. — Snout usually rather blunt; nostril anterior to nasal 

 suture; anterior nasal usually not in contact with second upper 

 labial; supraoculars 3-5, normally 4; position of supraocular granules 

 variable; frontoparietals normally 2; parietals usually 3; occipitals 

 small ; anterior gulars moderate, uniform or somewhat enlarged cen- 

 trally; posterior gulars smaller, more or less uniform, and sometimes 

 not abruptly separated from anterior gulars; mesoptychial scales 

 variable, but usually smaller at edge. 



Body elongate; ventral plates in 8 longitudinal and 2G-39 trans- 

 verse rows; dorsal granules small to moderate, variable; limbs well 

 develoj)ed; brachials 4-9; antebrachials 2-5; brachials and ante- 

 brachials more or less continuous at a point of contact; postante- 



