19221 



Schmidt, Amphibians and Reptiles of Lower California 



643 



The Albatross Expedition in 1911 secured forty-one specimens of this 

 large lizard from San Esteban. Comparison with S. hispidus from Angel de 

 la Guardia, S. ater from the peninsula, and S. obesus from California proves 

 that it is quite as distinct a species as S. hispidus. From S. obesus it is 

 distinguished by the distinctly smaller auricular spines and the smaller 

 number of ventral scales, from S. ater by the large size and coloration, 

 while from S. townsendi and S. hispidus, it is readily distinguished by the 

 non-spinose nuchals. 



In coloration the species is strikingly distinct from the much darker 

 adults of obesus and hispidus. I have no large specimens of S. ater and 

 S. townsendi but neither of these species shows any trace of the blotching 

 of S. varius. The dorsal dark patches take on most irregular shapes and 

 arrangements, never symmetrical, sometimes ill-defined, sometimes 

 rather sharply set off from the ground color. Ventrally, the color is 

 yellowish with a few small dark spots. Even on the tail the arrangement 

 of the dark color is not symmetrical, as in juvenile hispidus. 



The Albatross Expedition visited San Esteban Island on April 13, 

 1911. Large numbers of the big spotted lizards of this species, as well as 

 of Ctenosaura hemilopha, were conspicuous, and were secured by pulling 

 them out from under the rocks where they took refuge, or by turning 

 over the rocks. 



Dr. J. N. Rose, who was a member of the party, has kindly identified 

 the stomach contents of three specimens. He writes: "The contents of 

 two stomachs are entirely made up of the flowers of Pachycereus pringlei 

 Britton and Rose. The third stomach is also largely filled with this 

 cactus flower, but also contains numerous small leaflets of some legumi- 

 nous plants, probably some CercidiumP 



Measurements and scale characters 

 species may be tabulated as follows. 



Total Length 



Tail-Length 



Tail-Length/Total Length 



Femoral Pores 



Dorsal Scales in Head Length 



Ventral Scales from Gular Fold to Anus 



Scales Around Thickest Part of Tail 



Sauromalus townsendi Dickerson 



Sauromalus townsendi Dickerson, 1919, p. 464. : 

 Range. — Tiburon Island; coast of Sonora? 



l Type: U. S. N. M. No. 64442. 



