REPTILES. 
39 
PLESTIODON FASCIATUS. 
Lacerta fasciata, Linn. Syst. Nat. I, 1758, 290. 
Scincus fasciatus, Holbrook, N. Am Herp. II, 1842, 127; pi. xviii. 
Lacerta quinquelincata, Linn. Syst. Nat. 1766, 366. 
Scincus quinquelineatus, Holbrook, N Am. Herp. II, 1842, 121; pi. xvii. 
Plcstiodon erythrocephilus, Holbrook, N. Am. Herp. 11, 1842, 117; pi. xvi. 
3176. Fort Smith. Dr. Shumard. 
PLESTIODON OBSOLETUS, B. & G. 
Plcstiodon obsoletum, B & G. Pr. A. N. Sc. VI, August, 1852, 129. 
3113. Coal creek, Arkansas. B. Mollhausen. 
This specimen is very young and is the only one in the collection which exhibits the typical 
coloration of the species. 
LYGOSOMA LATER ALE, Dum. Bib. 
Scincus lateralis , Say, Long’s Exped. II, 1823, 324.— Holbrook, N. Am. Herp. II, 1st ed. I, 1836, 71. 
Lygosoma lateralis, Duiu Bib Erp. Gen. V, 1839, 719.— Holbrook, N Am. Herp. II, 1842, 133; pi. xix. 
3132. Fort Inge, Texas.—3135. San Antonio. Dr. Kennerly. 
CROTALUS DURISSUS, L i n n.— Rattlesnake. 
Crotalus durissus, Linn. Syst. Nat I, 1766, 372.— Holbrook, N. Am. Herp. Ill, 1812, 9; pi. i.—B. & G Catal. 
N. Am. Serpents, 1853, 1. 
Spec. Char. —Head small, narrow; superciliaries, frontals, and other large plates smooth and uncorrugated. Suh-orbital 
chain continuous; two rows between this and the labials. Labials 12-14 above, 13-16 below. Dorsal rows of scales 23-25, all 
carinated ; carinations of outer row obsolete. No defined light lines on head or body, and no lighter edgings to the plates of the 
head ; tail black. Above yellow or yellowish brown, with a double dorsal series of brown or blackish confluent rhomboids, with 
another series opposite on each side. A distinct narrow reddish dorsal stripe, three or four scales in width from head to tail. 
A broad dark stripe from the lower and posterior angle of the orbit across the angle of the mouth ; this stripe sometimes 
obsolete.—(Kennicott.) 
No. 277. Fort Smith, Arkansas. Dr. G. G. Shumard. 
CROTALUS ATROX, B. & G. 
Crotalus atrox, B & G. Catal. N. Am. Serp. 1853, 5. 
Spec. Char —Nose broad, obtuse. Plates of head elongated and much imbricated; two rather small anterior frontals in 
contact; two larger imbricated places between these and each superciliary; space enclosed occupied by scales of smaller size 
but larger than those between the posterior half of the superciliaries. Superciliaries usually bordered by a row of larger 
scales, of which the anterior is much largest. All the larger plates of the crown very much corrugated, and the anterior plate 8 
generally with their edges turned up ; this, together with their corrugated surfaces, presenting a very rough appearance. Three 
rows of scales between the sub-orbital clraiu and labials. Labials 15-16 above, 15-17 below. Dorsal rows 25-27; central row 
strongly carinated, with additional small ridges converging to the apex of each scale. Tail with black rings. Color dull 
yellowish brown, with a dorsal series of rhomboidal blotches, margined by lighter lines much the same as in C. adamanteus, but 
t he lateral markings represented in C. adamanteus all obsolete. Abdomen without spots. A single transverse light line on the 
superciliary, sometimes obsolete. Light stripe from posterior angle of orbit below' the superciliary to the upper labials in front 
of the angle of the mouth. No light lines in front of the nostril, or light edgings on rostral —(Kennicott.) 
No. 4225, Rocky Dell creek, Indian territory. B. Mollhausen. 
