146 BULLETIlSr 15 4, UNITED STATES NATIONAL MUSEUM 



stripes in JahlaUs suggests hyperi/thrus, but the structural affinities, 

 as well as other colorational features, are with perplexits. This inter- 

 mediate coloration, and the normal possession of two frontoparietal 

 plates, make it fairly certain that the ancestral lahlalis-liy perythrus 

 stock came from an ancient form very much like the present per- 

 plexus. It is believed that Jab lolls became independent, when a sec- 

 tion of this stock gave rise to the hnmediate ancestral population of 

 hyperytlu-us through the union of the frontoparietal elements. 



latiaUs-" perp\exus -« quleirvs ►sejclvneaKAs 



Ancestral 



^gAl\-nealus 



slock 



I'lcruK L't;. -A i>i.M:KA.%r (H' the .si;pp(isei) kei.ationshu's within thk skxi.inkati's 



CKOCl" 



The writer's interpretation of the genetic relationships within the 

 sexlineatus group are expressed by the foregoing diagram. 



THE TESSELLATUS GROUP 



CNEMmOPHORUS TESSELLATUS TESSELLATUS (Say) 



DESERT WHIPTAIL, TESSELLATED LIZARD, TIGER LIZARD 



1823. Amciva tvasduia Say, Long's Exp. llocky Mts., vol. 12, p. 50 (tyi)e locality, 

 "Arkansas River, near Castle Rock Creek, Colorado"). — Hahlan, Journ. 

 Acad. Nat. Sci. Pliila., vol. G, 1827, pp. 8, 37. — Gray, Synops. Reptilia, appx. 

 to Griffith's " Cuvier's ' Animal Kingdom '," 1831, p. 30. — Haelan, Med. and 

 Phys. Researches, 1835, pp. 130, 162. — Baiiu) and Gikard, Reptiles, in Stans- 

 hury's " Expl. and Surv. of the Valley of the Great Salt Lake of Utah," 

 appx. c, 1852, p. 338.— Hallowell, Proc. Acad. Nat. Sci. Phila., 1854, p. 94; 

 Reptiles, Pacific R. R. Surv. (Williamson route), vol. 10, pt. 4, no. 1, 1859, 

 p. 9. 



1834. Amcviain icssvlatuiit Wiegmann, Herpetologia Mexicana, p. 27 (footnote). 



1842. Amoiva tesscUata Db Kay, Zool. of N. Y., pt. 3, Reptiles and Amph., 

 p. 30.— Garman, Bull. Essex Inst., vol. 16, 1884, p. 12. 



1852. Cnemidoplwriis tesselatus Baird and Gibard, Reptiles, in " Stansbury's 

 ' Expl. and Surv. of the Valley of the Great Salt Lake of Utah '," appx. c, 

 p. 338.— Baikd, Reptiles, Pacific R. R. Surv. (Gunnison and Beckwith routes), 

 vol. 10, pt. 5, no. 3, 1859, p. IS.— Gadow, Proc. Roy. Soc London, vol. 72, 1903, 

 pp. 110, 121. 



1852. Cneniidophorus yraclUs Baiud and Gikakd, Proc. Acad. Nat. Sci. Phila., 

 p. 128, (type locality, "Desert of Colorado"; type specimen, U.S.N.M. No. 

 3034, J. L. LeConte, collector) ; Proc. Acad. Nat. Sci. Phila., 1852, p. 301 ; Rep- 

 tiles, Expl. Red River of La. (1852), 1853, p. 239.— Baird, Reptiles, Pacific 

 R. R. Surv. (Gunnison and Beckwith routes), vol. 10, pt. 5, no. 3, 1859, p. 10. — 

 Cope, Proc. Acad. Nat. Sci. Phila., 1863, p. 104; 1866, pp. 310-311.— Peters, 

 Monatsber. Berl. Akad. Wiss, 1869, p. 63.— Gunther, Zool. Rec. for 1869, 

 vol. 6, 1870, p. 111.— Cope, Bull. U. S. Nat. Mus., vol. 32, 1887, p. 45. 



