226 BULLETIN 15 4, TTNITKH STATES NATFOXAL T\rTTSKTTl\r 



closely. Both arespotlcd and show no (I'accs of IIk' rcticiihitions that 

 are so characteristic oi' inartijiis and caiuus. However, it seems prob- 

 able that their pattern has been derived from that of these reticu- 

 lated lizards by the breaking apart and concentration of the light 

 pencilings into small distinct spots. ]\Ioreover, the pattern and per- 

 haps the geographical position of hacatus and cataVinenxh are snch 

 as to suggest derivation from inartyris rather than from tcssellatus. 

 As to the immediate origin of eacli, geographical position seems to 

 favor the derivation of catalinensis from hacatus, although ])ossibly 

 both forms are the remnant of a common stock which may have cov- 

 ered a rather extensive area in wliat is now the Gulf of California 

 j)rior to its more complete submergence. It is apparent that active 

 ditferentiation of these forms from each other has taken place in 

 relatively recent times, probal)ly in the post-Pk'istocene. 



The writer's interpretations of the genetic relationships within the 

 tessellatu,^ group are expressed by the foregoing diagram. 



THE HYPERYTimUS GROUP 



CNEMIDOPHORUS HYPERYTHRUS HYPERYTHRUS (Cope) 



WESTERN ORANGE-THROATED RACE-RUNNER 



1SG,3. Ciicmidophorus hi/periithrus Cope, Proc. Acad. Nat. Sci. Phila., p. 103 

 (type locality, "Cape St. Lucas. Lower California," Mexico; type specimen, 

 U.S.N.M. No. 5209, John Xantus, collector) ; Proc. Acad. Nat. Sci. Phila., 

 1S6G, p. 312; Proc. Amer. Philos. Soc, vol. 11, 1869, p. 15S.— Giintiieb, Zool. 

 Rec. for 1869, vol. 6, 1870, p. 111.— Boulenger, Cat. Liz. British Mus., vol. 2, 

 1885, p. 371.— Stbjneger, Proc. U. S. Nat. Mus., vol. 12, 1890, p. 644.— Bout>- 

 ENGER, Proc. Zool. Soc. Loudon, 1898, p. 910. — Mocquard, Nouv. Archives dxi 

 Mus., Paris, ser. 4, vol. 1, 1899, p. 314.— Gadow, Proc. Zool. Soc. London, 1900, 

 p. 307. — DiTMARS, Reptile Book, 1907, p. 185. — Brown, Proc. Acad. Nat. Sci. 

 Phila., 1908, p. 118. 



1869. Verticaria Jiyperi/fhra Cope, Proc. Amer. Philos. Soc, vol. 11, p. 158 ; 

 Bull. U. S. Nat. Mus.. no. 1, 1875, p. 46.— Yarrow, Bull. U. S. Nat. Mus., no. 

 24, 1882, p. 45.— Cope, Proc. Acad. Nat. Sci. Phila., 1883, p. 32; Bull. U. S. 

 Nat. Mus., no. 32, 1887, p. 45.— Stejneger, Proc. U. S. Nat. Mus., vol. 17, 1894, 

 pp. 17-18. — Van Denburgh, Proc. Calif. Acad. Sci., ser. 2, vol. 5, 1895, pp. 

 128-130.— Cope, Amer. Nat., vol. 30, 1896, p. 1013.— Boulenger, Zool. Rec. 

 for 1895, vol. 82, " Reptilia," 1896, p. 19.— Belding, W. Amar. Sci., vol. 3, 

 1879, p. 97.— Cope, Ann. Rep. U. S. Nat. Mus. for 1898, 1900, p. 563.— Van 

 Denburgh and Slevin, Proc. Calif. Acad. Sci., ser. 4, vol. 11, 1921, p. 98. 



1884. Cnemidophorus hupcrethra Garman, Bull. Essex Inst., vol. 10, p. 13. 



1894. Verticaria heJdingi Stejneger, Proc. U. S. Nat. Mus., vol. 17, ]). 17 (type 

 locality, " Cerros Island, Lower California," Ml'xIco ; type specimen, U.S.N.M. 

 No. 11980, L. Belding, collector).'* 



^ As will be seen by the following statements, there lias been some uncertainty con- 

 cerning the type lots of lahialls and heldingi. In answer to the writer's inquiries, Doctor 

 Stejneger, under the date of Feb. 21, 1029, has furnished an account which malies the 

 liistory of these specimens clear. It may be quoted in full as follows: "(1). In the 

 original record book there was entered during November, 1881 (eight years before I had 



