1885.] 4^^^ [Cope. 



the groin, black ; chin, throat and sides blue. The collar is a continua- 

 tion of the black of the thorax. 



Length of head and body to vent, M. .116 ; length of head to posterior 

 line of auricular meatus, .028 ; length of posterior leg, .068 ; of hind foot, 

 .031 ; of tibia, .026. 



A male specimen of this species was sent to the National Museum by 

 Dr. Duges of Guanajuato, Mexico. Associated with it is another speci- 

 men apparently of a variety of the S. torquatus, with which it agrees in 

 all essential characters. Nevertheless, it agrees with the S. melanog aster 

 in the character of its collar and the borders of it. The color below is 

 yellow, with the throat and chin marbled with a very pale blue, between 

 yellow scales. The dorsal region is light brown, and there are four rows- 

 of dark brown spots. There are two canthal plates and one row of large 

 supraoculars. No. 9877, National Museum ; from Dr. Alfredo Dug^s. 

 Probably from Guanajuato. 



ScELOPORUS SERRiFER Cope, Procccds. Academy Philada., 1866, p. 124. 

 This species is, as supposed by Bocourt, nearly allied to the S. torquatus. 

 Of four adults specimens, three have the collar interrupted, and one has it 

 continuous over the nape. In three young specimens the collar is unin- 

 terrupted. In none of the adults are there more than ten femoral pores. 



Yucatan, Seliott. 

 SCELOPOKUS ACANTHiNUS Bocourt, Missiou Scientifique Mexique, iii. Rep- 

 tiles, 180 ; pi. xviii, figs. 10, 10a, lOJ ; xix, figs. 4, 4a. 

 St. Augustino, West Gautemala, Gommision Scientifique. 

 ScELOPORUS TORQUATUS Greene and Peale ; Agama torquata Greene and 

 Peale, Journ. Acad. Phila., t. vi, 1827-1828, p. 231 ; Sceloporvs torqua- 

 tus Wiegmann, Isis, 1828, p. 369 ; Tropidurus, Sceloporus torquatus 

 Wiegm., Wagler. Syst. Amph., 1830, p. 146; Tropidolejns torquatus 

 Gray, Synops. in Griffith's Anim. King., t. ix, 1831, p. 43. Sceloporus 

 torquatus Wiegmann, Herp. Mex., pars, i, 1834, p. 49, tab. vii, fig. 

 1 ; Tropidolepis torquatus Dum. et Bibr., Erp. Gen., t. iv, 1837, p. 301 ; 

 Sceloporus torquatus Fitzinger, Syst. Kept., 1843, p. 75 ; Tropidolepis 

 torquatus Gray, Cat. spec. Liz., 1845, p. 208 ; Aug. Dumeril, Cat. meth. 

 coll. Rept., 1851, p. 77 ; Sceloporus formosus Wieg., Herp. Mex., 

 pi. i, 1834, p. 50, tab. vii, fig. 2 ; Tropidolepis formosus Dum. et 

 Bibr., Erpet. Gener., t. iv, 1837, p. 303 ; Sceloporus formosus Fitzinger, 

 Syst. Rept.., 1843, p. 75 ; Tropidolepis formosus Gray, Cat. Liz., 1854, 

 p. 209 ; Aug. Dumeril, Cat. meth. coll. Rept., 1851, p. 77. Sceloporus 

 formosus Bocourt, Com. Sci. du Mexique, iii Rept., p. 182, pi. xviii, 

 fig. 3, 3a, 3b, 3c. Sceloporus poinsettii Baird and Girard, Proc. 

 Acad. Phila., 1852, p. 126 ; U. S. and Mex. Bound. Survey, 1859, p. 

 5, pi. xxix, figs. 1-3. Bocourt, Miss. Sci. du Mex., iii Rept., p. 171, 

 pi. xviii, fig. 9, 9a, 9b, 9c. 

 Colima, Duges ; Oaxaca, Boucard ; Xalapa, Keating, Montesdeoca ; 

 Vera Cruz, Sartor ius ; Monterey and Laredo, Cope ; Texas, Clark. 



PROC. AMER. PHILOS. SOC. XXII. 120. 2y. PRINTED JULY 29, 1885. 



