354 PROCEEDINGS OF THE NATIONAL MUSEUM VOL, 92 
average 31.9; while 49 f. formosus show a range of from 82 to 37 (82, 8; 
33, 11; 34, 9; 35, 11; 36, 6; 37, 4), average 34.2. 
The only difference of recognizable significance between the two 
races is in pattern; in this there is a very striking divergence between 
them. Males, females, and young of f. formosus lack the longitudinal 
light and dark lines on the neck, and the scattered light spots on the 
head, of 7. scitulus; and the adult males of the former are blue, not 
green as in the Guerrero race, lack the longitudinal dark lines on the 
dorsal surface of the body and have a broad yellow or orange area 
on the middle of the throat. In males of 7. scitulus yellow or orange 
on the throat is completely absent, the whole throat being blue. 
Remarks.—The race f. scitulus is illustrated in The Mexican and 
Central American Lizards of the Genus Sceloporus.! 
SCELOPORUS PREZYGUS, new species 
Holotype—uU.S.N.M. No. 46881, from Conjab, 5,300 feet, Chiapas 
(between San Bartolomé and Comitin). Collected by E. W. Nelson 
and E. A. Goldman. 
Diagnosis —A member of the formosus group, with 31 dorsal scales, 
supraoculars in 2 rows, 13 to 14 femoral pores, 2 canthals and median 
frontonasals separated from lateral frontonasals. 
Description of holotype-—Head somewhat flattened and elongate; 
interparietal about three times as large as a parietal; a single parietal 
on each side, but little larger than a frontoparietal; latter single on 
each side; frontal narrowly in contact with interparietal; supraoculars 
in two rows; the scales of the inner row about twice as large as those 
of outer row, which is composed of three scales; supraoculars separated 
from median head scales by a complete row of granular scales, from 
superciliaries by one complete and another incomplete row of small 
scales; frontal in contact with median frontonasal; latter consider- 
ably larger than lateral frontonasals, separated from them by a small 
scale; scales in internasal area large, keeled, pitted, three from median 
frontonasal to rostral; two canthals; a large, elongate subnasal; three 
small loreals; preocular longitudinally divided, a large upper and 
small lower scale; an elongate subocular and two keeled postoculars; 
two complete rows of lorilabials below subocular; four supralabials 
and five infralabials to a point below middle of eye. 
Two rows of labiomentals, the outer not reaching mental, the inner 
extending anteriorly to a point even with the suture between the sec- 
end and third infralabials; posterior gulars notched; temporal scales 
keeled, very feebly mucronate; three small auricular lobules, upper 
largest; scales between ear and lateral nuchal pocket more strongly 
*Field Mus. Nat. Hist., zool. ser., vol. 26, pl. 1, 1939. 
