No. 50.] 107 



Stn. Crotalopkorus, G-ray, Ann. Pbilos. 1825, 205.— B. & Gr. CataL 

 of North-American Serpents, 1853, 1. 



2. Crotalophorus tergeminus, Holbr. — Massasauga. 



Spec. Chak. Twenty-five rows of dorsal scales, strongly carinatecl,witli the excep- 

 tion of the first row, which is perfectly smooth. Vertical plate subhexagonal, 

 pointed posteriorly. Seven longitudinal series of blotches. A narrow hand of 

 yellowish white extends from the pit to the neck, in passing close to the angle of 

 the mouth, 150, 21+1, 25, 29^, 2^ (Wisconsin). 



SYNONYMS. 



Crotalus tergeminus, Sat, Long's Exp. Rocky Mts. I. 1823, 499. — Haul. Journ. 



Acad. Nat. Sc. Philad. Y. iii. 1827, 372. 

 Crotalophorus tergeminus, Holbk. N. Amer. Herp. III. 1842, 29. PI. v. — B. &.G. 



Catal. N. Am. Serp. (1853), 1— Gebh. 6th Rep. State Cab. Nat. Hist. 1853,22. 

 Crotalophorus, Agass. Lake Sup. 1850, 381. PL vi. fig. 6-8. 

 Prairie Rattlesnake, Massasauga. 



As this species is not included in Dekat's Fauna of New- York, I give a 

 detailed description, taken from a specimen caught in Wisconsin ; referring 

 to the Report of the State Cabinet as above quoted, for the description of 

 the New- York specimen. 



The ground color above is brown : the blotches are deep chestnut-brown, 

 blackish externally, and with a yellowish white margin. The dorsal blotches 

 are thirty-four in number from the head to the region opposite the anus, 

 twenty-six of which are transversely and irregularly oblong, anteriorly and 

 posteriorly emarginated ; less so, however, posteriorly : eight are subcircu- 

 lar. Five or six exist on the tail from the anus to its tip, extending on the 

 sides, the last two forming sometimes a complete ring. The next series on 

 either side is composed of small blotches, but as intensely colored as in the 

 other series : they alternate with the dorsal ones : they have no regularity 

 either in outline or position. The second lateral row is composed of the largest 

 lateral blotches : they are transversely oblong or oval on the second, third, 

 fourth, fifth, and sixth rows of scales, and opposite the blotches of the dorsal 

 series ; consequently alternating with the third series above. The first lateral 

 series again is composed of blotches intermediate in size between those of the 

 third and second series : they occupy the first and second rows of scales, and 

 extend somewhat to the abdominal scutell^e, and alternating with the ad- 

 joining series. Two undulated vittas extend from the supraorbital plates along 

 the neck to the first dorsal blotch, and often confluent with the latter. A 

 linear vitta, margined with yellowish white, extends from the posterior edge 



