36. RHINOCHEILUS 775 



Soc. Nat. Hist., Vol. Ill, No. 4, 1921, p. 64; VAN DENBURGH & 

 SLEVIN, Proc. Cal. Acad. Sci., Ser. 4, Vol. XI, 1921, p. 40, 45, 52; 

 NELSON, Mem. Nat. Acad. Sci., Vol. XVI, 1921, pp. 114, 115. 



Description. Head rounded and snout projecting and 

 pointed. Temporal regions not swollen. Rostral plate 

 large, prominent, recurved on top of snout, and bounded 

 behind by internasal, anterior nasal, and first labial plates. 

 Plates on top of head, a pair of internasals, a pair of pre- 

 frontals, a broad frontal, supraocular of each side, and a pair 

 of rather short, rounded parietals. Anterior and posterior 

 nasals usually distinct, but sometimes united above nostril. 

 Loreal small, elongate, sometimes entering orbit. One or 

 rarely two preoculars and two or rarely three, postoculars. 

 Temporals normally two followed by three, rarely 2+2, 

 1+3, or 2+4. Eight (rarely seven or nine) superior and 

 eight, nine or 10 inferior labials, seventh (or eighth) super- 

 ior and fifth (or sixth) inferior largest, fourth and fifth (or 

 fifth and sixth) superior reaching eye, first pair of inferior 

 meeting on median line. One or two pairs of genials, 

 posterior very narrow when present. Scales on body smooth, 

 thin, in 23 or rarely 25 rows. Anal plate not divided. 

 Gastrosteges varying in number from 1 86 to 216. Urosteges 

 in one series, or more often in one series anteriorly and two 

 posteriorly, of from 40 to 55. 



The snout is yellowish more or less marked with black. 

 Back of this the head is black or brown, often spotted with 

 yellow or white. Across the back is a series of large black 

 or brown blotches; 20 to 34 on the body and 6 to 12 on the 

 tail. These blotches may be rounded, pointed, or truncate 

 on the sides, and are from one and one-half to three times 

 as long as the intervals which separate them. These inter- 

 vals are brick red, orange, yellow, or white, and usually 

 are continuous with the white or yellow of the lower 

 surfaces. 



