42 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 66 



sian herpetologists as containing more than three times as many 

 species and subspecies. Thus Beclriaga, who in 1907-1909 published 

 an elaborate account which amounts to a monograph of the genus, 

 after an examination of about 1,350 specimens ^^ recognized 44 species 

 and numerous subspecies. The genus, which in many ways shows 

 analogies with the American Iguanoid genus Phryi^osoma^ is con- 

 fined to the Asiatic desert regions, from the Caspian Sea in the 

 west almost to the Pacific Ocean in the east. Only recently Mr. 

 Sowerb}^ has confirmed its occurrence in China proper, though it has 

 been known for many years from the adjacent Mongolian provinces, 

 where numerous forins have been discovered by Russian explorers, 

 such as Przhevalski, Potanin, and others. 



A single Phrynocephalus collected during the expedition of 

 Count Bela Szechenyi at " Quan-joan-shin (Kwang-yuen) " in the 

 province of Szechwan, was identified and recorded by Steindachner 

 as Phrynocephalus caudivolvolus^^'^ the first record of a Phrynoce- 

 phalus from Avithin the boundaries of China proper. That it is not 

 Ph. caudivolvolus., as at present restricted and understood, is certain, 

 but only a reexamination of the specimen can decide to which of the 

 many related forms it belongs. 



PHRYNOCEPHALUS POTANINI Bedriaga 



1907. Phrynocephalus potanini Bedriaga, Wiss. Res. Przewalski Central- 

 Asien Reis., Zool., vol. 3, sect. 1, Arnph. Rept., pt. 2, Nov. 9, 1907, p. 

 144; pt. 3, June 20, 1909, p. 389, pi. 6, figs, l-lh (type locality, Hwangho 

 and Ulan-Muren River, Orclos, China ; types, Nos. 7443 and 7438 Mus. 

 St. Petersburg; Potanin, collector). 



1912. Phrynocephalus frontalis Sowerby, iu Clark and Sowerby, Througli 

 Slien-Kan, 1912, p. Ill (Yulinfu, Shensi) (not of Strauch). 



With the material at hand there is no difficidty in recognizing that 

 the two series, collected by Sowerby in two provinces, represent two 

 ditf'erent forms, though undeniably they are closely allied and belong 

 to the Ph. caudivolvulus group. On direct comparison it is plain that 

 in one the nostrils are relatively closer together than in the other; 

 one also has a higher head, and possibly the outline of the snout is 

 somewhat different. One has slightly larger scales than the other, 

 but when reduced to actual measurements the figures run together. 

 This does not mean that the two forms are connected b}' " intermedi- 

 ates." Viewed together, as groups or individually, the observer has 

 no difficulty in distinguishing them. In this particular instance it so 

 happens that the species with the narrow internarial space has the 

 larger dorsal scales, and it is thus possible to separate the two series 



^ Wiss. Result, rrzewalski Central-Asien Reis., Zooi., vol. 3, Sect. 1, Amph. Rept., pt. 

 2, 1907, aiul pi. 3, 1909, pp. 134-500, pis. 3-7 and 9. 



•''"Wiss. Ergebn. Reise Szechenyi Ost-Asieii, vol. 2. 1898, p. 505; Hungarian Edition, 

 1S97, p. 651. 



