POISONOUS SNAKES OF NORTH AMERICA. 413 



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

 brown, blackish externally, and with a yellowish-white margin. The 

 dorsal blotches are 34 in number from the head to the region opposite 

 the anus, 26 of which are transversely and irregularly oblong, anteriorly 

 and posteriorly emarginated^less so, however, posteriorly; 8 are sub- 

 circular. Five or (» 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 tlie largest lateral blotches. They are transversely 

 oblong or oval on the secoud, third, fourth, lifth, and sixth rows of scales, 

 and opposite the blotches of the dorsal series; consequently alternating 

 with 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 secoud rows of scales, and extend 

 somewhat to the abdominal scutelhi', [ventrals, or gastrosteges], and 

 alternating with the adjoining series. Two undulated vittjB extend 

 from, the supraorbital i)hites along the neck to the first dorsal blotch, 

 and often confiuent with the latter. A linear vitta margined with yel 

 lowish white extends from the i)Osterior edge of the eye to the sides of 

 the neck; the inferior yellow margin is the broadest, and passes from 

 the pit close to the angle of the mouth, turning forward to the middle of 

 the lower jaw, inclosing a semielliptical brown patch. Two elongated 

 yellowish spots may be observed diverging from both sides of the pit to 

 the lip. The cephalic plates are deep chestnut-brown; a transverse 

 light brown band extends across the head from one orbit to the other. 



Variation. — The ground color varies from brownish gray, through 

 brown, to blackish, the latter being the so called C. kirtlandi. It 

 ajipears that specimens living in swamps and marshy places are chiefly 

 of the latter color. The alleged differences in the shape of the head 

 between Ohio and Wisconsin specimens (Smith, loc. cit.) I have been 

 unable to verify. 



Geographical (listrilmtion. — The area inhabited, now or formerly, by 

 the Massasauga lies approximately between the seventy-seventh and 

 ninety-eighth meridians and the thirty-eighth and forty-fifth parallels. 



In the State of New York theyhave been found in Genesee County, 

 in the western portion, draining into Lake Ontario, where their occur- 

 rence in the town of Byron was recorded for the first time in 1853 by 

 Mr. John Gebhard. They then inhabited a white-cedar swamp con- 

 taining an area of about 1,000 acres. In Ohio, whence came the 

 types of Kirtland's G. messasaugus (or Holbrook's C. Mrtlandi), they 

 are presumed to occur in all parts. It is also common in parts of 

 Michigan, though it must be remembered that this expression " com- 

 nmn" in all these snakes is a very indefinite term. The accessible rec- 

 ord may show them to have been common in a given place at the time 



