SYNOPSIS OF GENERA ANB SPECIES 



OP 



NEW-YORK SERPENTS 



Genus CROTALUS, Linn. 



Gen. Char. Upper surface of head covered witli small plates, scale-like, 

 witt a few larger ones in front. The tail is terminated by a well deve- 

 loped rattle. A deep pit between the eyes and the nostrils. Subcaudal 

 scutelbe entire* Temporal and labial shields small and convex. 



1. Crotalfs DifElssus*, L. — Ptattlesnake. 



Spec. Char. Head angular. Scales between the snperciliaries small, numerous, 

 uniform. Plates above snout, 2 anterior frontal, and 5 postfrontal. Suborbital 

 chain continuous, of large scales : two rows between this and labials. Labials 

 12 - 14 above, fifth largest] 13 - 15 below. Eows of scales on the back 23 - 25, 

 all carinated : carination on outer row obsolete. Tail black. Above sulphur- 

 brown, AVith 2 rows of confluent broAvn lozenges. Light line from superciliary to 

 angle of the mouth: behind this a dark patch. 166, 25, 23j 42, 5 (Pennsylvania). 



SYNONYMS. 



Crotalus durissus, Linn. Sy.st. Nat. I. 1766, 372. — Gm. Linn. Syst- Nat. ed. xiii. 

 I. iii. 1788, 1081.— HoLBR. N. Amer. Herp. III. 1842, 9. PL i.— Dekat, 

 N. Y. Fauna, Pt, III. 1842, 55. PI. ix. fig. 19.— S*orer, Rep, Kept, of Mass. 

 1839, 233.— Baird & Girard, Gatal. N. Am. Serpents, 1853, 1. 



Vipera caudisona americana, Catesb. Nat. Hist. Carol. II. 1743, 41. PI, Ixi. 



Northern Rattlesnake. 



The Cr'jtalus durissus, or northern rattlesnake, is more extensively dis- 

 tributed throughout the United States than any other of the genus* It ia 



• The numbers preceding the specific name are ihe same with the corresponding figures on the plates. 



