286 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ne 



acter (fig. 8). Since U. oniatus is gi-eatly in need of a modern 

 systematic revision, I hold subspecific allocation of Zuni specimens 

 tentative at this time. 



Using Oliver's methods (1943, pp. 100-101), the following may be 

 noted m U. ornatus from the Zunis. Enlarged dorsal scales are 

 present in two distinct rows on each side of the smaller vertebrals in 

 28 percent of a series of 29 specimens; they are in two rows with 

 additional enlarged dorsals tending to form a third outer row in 66 

 percent and in three quasi-distinct rows in 6 percent. Carination of 

 these scales varies from a flat, weak keel to a sharp raised point with 

 all types of intermediate forms observable. Similarly, complete 

 gradation in the merging of dorsal tail-base scales with adjacent 

 scutes is present. Thirty-one percent of the specimens have the 

 enlarged dorsals separated by two rows of small vertebral scales, 

 while 69 percent possess only one row of vertebrals. 



[j i gD 



16 



liil 



__ 17 



25 



B I J||li l iilllll l I 17 



19 



30 35 40 45 50 55 60 



DORSAL SCALES 



Figure 8. — Variation in the number of enlarged dorsal scales of Urosaurus ornatus from 

 Arizona, New Mexico, and Utah. (Horizontal line = range; vertical line = mean; solid 

 bar=two standard errors of the mean; hollow bar = one standard deviation. Sample 

 size to right of range; provenance of sample to left: A, Pima and Santa Cruz Counties, 

 Arizona; B, Cochise Co., Arizona; C, Yavapai Co., Arizona; D, McKinley and Valencia 

 Counties, New Mexico; E, Kane Co., Utah; F, San Juan Co., Utah.) 



Thirteen individuals from the northeast of the Zuni Mountains 

 have 40-53 (x 44.5 ±0.96) enlarged dorsals from the anterior insertion 

 of the forelimbs to anterior insertions of hindlimbs; 16 from the 

 southwest side have 35-47 (42.3 ±0.95). If these counts are com- 

 pared with those of U. ornatus from Utah and Arizona, a north-south 



