40 PROCEEDINGS OP I HE NATIOlsTAL MUSEUM vol.73 



CTENOSAURA PALEARIS Stejneger 



Plates 22, 23 



Ctenosaura palearis Stejneger, 1899, Proc. U. S. Nat. Mus., vol. 21, pp. 381- 

 383; 1901, vol. 23, pp. 467-468. 



Type.— Csit. No. 22703, U.S.N.M., male. 



Type locality. — Gualan, Guatemala, 1899; Mrs. K. I. P. McElroy, 

 collector. 



Diagnosis. — A large dewlap hanging from posterior part of throat; 

 caudal whorls of spines separated by a single row of flat scales; 

 upper side of tibia covered with large hexagonal scales, each armed 

 with a central spine; dorsal crest high, but composed of 35 to 45 

 spines only; interrupted in the sacral region. 



Distribution. — This species inhabits the dry flat sandy zone of 

 Guatemala in the vicinity of Gualan, at an elevation of from 1,000 

 to 2,000 feet. It has been taken at Gualan, and at Cuastotoya, 

 Jalapa, Guatemala. These two points represent a very restricted 

 area lying just south of the Motagua River. 



Description. — The following description of the type specimen, an 

 adult male. Cat. No. 22703, U.S.N.M., is from Doctor Stejneger's 

 original paper. 



Head rather short; muzzle with decurved profile, covered above with rather 

 large and slightly rugose scales; supraoculars small, nearly granular externally, 

 larger, hexagonal and flat internally, separated from each other by three rows of 

 scales; parietal scales slightly smaller than those on top of muzzle, tubercular; 

 nostrils large, much nearer the tip of snout than the orbit, almost tubular, opening 

 obliquely backward; behind nostrils a large, flat scale; one or two canthal scales; 

 lores flat; temporals slightly smaller than the occipitals, tubercular; 10 or 11 

 enlarged supralabials; 9 enlarged sublabials; ear opening as large as orbit; dorsal 

 scales small, hardly more than half the size of the ventral scales, gradually increas- 

 ing in size posteriorly, smooth; a well developed dorsal crest, barely indicated on 

 the rump. The spines of the crest, 45 in number, all told, begin almost immedi- 

 ately behind the head; first six spines very small, followed by two somewhat larger 

 ones; ninth is suddenly larger and tenth still larger, equaling the largest; the 

 spines are very compressed, about 8.3 mm. (0.325 inch) high and 3.8 mm. (0.15 

 inch) wide at base, and falcate in shape; their base is flexible and covered for 

 about one-fourth of their height with two to three rows of minute scales; the 

 last 12 spines decrease gradually in size, the last being equal to the first ones on 

 the nape; about 10 small carinated scales follow until the caudal crest begins; 

 three transverse dermal folds across the throat which, with a similar one behind 

 the ear, join two longitudinal folds on the side of the neck; these extend back- 

 ward over the shoulder for some distance; between the anterior and posterior 

 transverse gular folds a large compressed dewlap 32 mm. (IJ^ inches) from 

 middle of base to top, the base along the middle of the throat being about 38 

 mm. (11/^ inches) ; scales on throat and dewlap slightly smaller than the ventral 

 scales, all smooth; scales on uj)per side of arm carinate, those on lower arm 

 slightly larger, more distinctly carinate and somewhat spinous at tip; scales on 

 femur slightly larger than ventral scales, those on the upper surface obtusely 

 keeled and with a small pointed tubercle at tip; scales on upper middle portion 

 of tiliia greatly enlarged, more or less regularly hexagonal, each with a falcate 



