1897.] LIZARDS OF THE GENUS SCBLOPORUS. 477 



B. Tail strongly compressed ; head-shields smooth. 



22. S. jn/rrhocephalus, Cope. 



C. Tail cylindrical; hind limb reaching beyond the eye; head-shields keeled 



or striated 23. S. chrysostictus, Oo'pe. 



II. Lateral scales longitudinal or nearly so ; series of femoral pores more or 



less narrowly separated, often meeting on the prseanal region ; head-shields 

 keeled or striated. 



Tibia shorter than the shielded part of the head. 24. S. csneus, Wiegm. 

 Tibia at least as long as the shielded part of the head. 



25. S. scalar is, Wiegm. • 



III. Lateral scales much smaller than, and abruptly differentiated from, the 

 dorsals. 



A. Lateral scales squamous, imbricate. 



1. 9-16 femoral pores on each side. 



46-6.5 scales between the interparietal shield and the base of the tail, 10-17 

 correspondiug to the length of the shielded part of the head. 



26. S. variabilis, Wiegm. 

 39-43 scales between the interparietal shield and the base of the tail, 8-9 



corresponding to the length of the shielded part of the head. 



27. iS'. cupreus, Bocourt. 



2. 3-8 femoral pores on each side ; 30-40 scales between the interparietal 



shield and the base of the tail. 



Two canthal scales ; ventral scales smooth ; male without enlarged postanal 

 scales 28. S. siniferus, Co])e. 



One canthal scale ; ventral scales obtusely keeled ; male without enlarged post- 

 anal scales 29. S.Julvus, Hoconvt. 



One canthal scale; ventral scales smooth ; male with enlarged postanal scales. 



30. S. squa^nosus, Bocourt. 



B. Lateral scales minute, granular. 



Head-shields keeled or striated ; 40 scales between the iuterparietal shield and 

 the base of the tail ; 13-14 femoral pores on each side. 



31. 8. iUiformis, Cope. 

 Head-shields smooth ; 82 scales between the interparietal shield and the base of 



the tail; 17-25 femoral pores on each side ... 32. S. couchii, Baird. 



1. SCBLOPOEUS TORQtTATTJS. 



Scelojoorus torquatus, Wiegm. Isis, 1828, p. 369, and Herp. Mei. 

 p. 49, pl.vii. fig. 1 (1834); Bocourt, Miss. Sc. Mex., Eept. p. 171, 

 pi. xviii. fig. 9 (1874) ; Cope, Proc. Amer. Philos. Soc. xxii. 1885, 

 pp. 169 & 401; Bouleng. Oat. Liz. ii. p. 219 (1885); Duges, La 

 Naturaleza, (2) i. 1888, p. 113 : Giinth. Biol. C.-Am., Eept. p. 66 

 (1890). 



Agama torquata, Green & Peale, Journ. Ac. Philad. vi. 1830, 

 p. 231. 



Tropidoleiiis torquatus, Gray, Griff. A. K. ix. Syn. p. 43 (1831), 

 and Zool. Beechey's Voy. p. 95, pi. xxx. fig. 2 (1839) ; Dum. & Bibr. 

 Erp. Gen. iv. p. 301 (1837); Gray, Cat. Liz. p. 208 (1845). 



Scelojoorus jpoinsettii, Baird & Gir. Proc. Ac. Philad. 1852, p. 126, 

 and U.S. Mex. Bound. Surv., Eept. pi. xxix. figs. 1-3 (1859); 

 Giinth. 1. c. p. 65. 



Pkoc. Zool. Soc— 1897, No. XXXIL 32 



