532 REPORT OF NATIONAL MUSEUM, 1898. 



The distribution of these species is as follows: 

 Medicolumbian Region. 



sonoran subregion. 

 B. imbricata; B. levicoUis. 



TOLTECAN SUBREGION. 



B. imbricata; B. rudicollis; B. planifrous; B. antaugvs. 

 Central American Region. 



guatemalan plateau. 

 B. fimbriata. 



The species of this genus are of plain colors, excepting those of Sec- 

 tion II, which are ornamental in their tints. The B. fimbriata of the 

 Guatemalan plateau has the same elongate supraauricular j)roces8es 

 as the Gerrhonotus auritus of the same district. 



BARISSIA IMBRICATA Wiegmann. 



Barissia imbricata Gray, Anu. Nat. Hist., 1, 1838, p. 390; Cat. Liz. Brit. Mus., 1845, 

 p. 55; Zool. Beechey's Voy., Rept.,p. 96, pi. xxxi, fig. 1. — Cope, Proc. Amer. 

 Phil. Soc, XVII, 1857, p. 97. 



Gerrhonotus imhricatiis Wiegmann, Isis, 1828, p. 381 ; Herpet. Mex., 1834, p. 34, pi. 

 X, figs. 2, 5. — DuMERiL and Bibron, Erp. Gen., V, 1839, p. 407. — Dugls, 

 Naturaleza, 1888, p. 121, pi. xii, fig. 9a; 1893, p. 294, pi. xii.— Gi nther, Biol. 

 C. Am. Kept., 1893, p. 38.— Bocourt, Miss. Sci. Mex., 1879, p. 363.— Bou- 

 lenger, Cat. Liz. Brit. Mus., II, 18n5, p. 272. 



Gerrhonotus licheniyerus Wagler, Descrip. et Icon. Amph., 1834, pi. xxxiv, 

 fig. 2. — Wiegmann, Herp. Mex., 1834, p. 35, pi. x, fig. 6.— Dumeril and Bib- 

 ron, Erp. Geii., V, 1839, p. 408. 



Gerrhonotus olicaceus Baird, Proc. Acad. Nat. Sci. Phila., 1858, p. 225; U. S. Mexi- 

 can Bound. Survey, II, Reptiles, 1859, p. 11. 



Head shields swollen. Ear aperture bordered in front by two or three 

 small scales and behind with granular ones. Nasal sei^arated from the 

 rostral. Four prefrontouasal and two internasals. A single nasoloreal. 

 No loreal. Dorsal scales imbricated and strongly keeled, a little larger 

 than the ventral plates. Lateral fold strong. Tail medium length. 

 Body with or without brown transverse bands in the male: two narrow 

 longitudinal yellow lines on the back of the female. 



Head-plates separated by strong grooves, causing inequality of the 

 surface. Length from end of muzzle to middle of ear equal to ten trans- 

 verse series of dorsal scales, and entering four and one-half times into 

 the space between the chin and anus. The muzzle supports two inter- 

 nasals, relatively well developed, situated to the right and left above 

 the nasal, and two large prefrontonasals, which are convex and longer 

 than wide, and truncate posteriorly. These plates are followed by two 

 l)retVontals which are angulate posteriorly, and which form a longi- 

 tudinal furrow, where they meet, along the median line on top of the 

 muzzle. Frontal flat and with the posterior angle truncated ; the inter- 

 parietal also flat, and with the frontal depressed so that the surround- 



