CROCODILIANS, LIZARDS, AND SNAKES. 



1189 



beiiitf worn off, bo that the imiiih«r of seniiieiits present is no indication jf the »<^e 

 of the snake. 



Holbrook stat'es that Mr. I'eah-, of tlie Phiiailolphia Musenni, kept a living female 

 rattlesnake for lourteen years. She had eleven rattles when she cauao into his pos- 

 session. Several were lost annually and new ones formed. When slu' died, there were 

 still eleven. During this period the snake had grown 4 inches in length. 



The number of young appears to be al)out nine. I found this number of eggs in a 

 female about .37 inches long, brought from Pennsylvania. The eggs were 1..5 inciies 

 long by an inch in diameter. Of these there were four in the left oviduct. There 

 were evidences that development had begun. 



Where these snakes are numerous, they are inclined to gather in considerable num- 

 bers in caverns in rocks and similar places in order to undergo their winter sleep. 

 Such places form the rattlesnake dens about which wo hear occasionally. 



CROTALUS ENYO Cope. 



Crotalus enyo Cope, Proc. Acad. Nat. Sci. Phila., 1861, p. 293.— Cupk, Check-list N. 

 Amer. Batr. and Rept., 1875, p. 33.— Van Denburgh, Proc. Cal. Acad. Sci., 

 1895, p. 157. 



Fig. 343. 

 Crotalus enyo Cope. 

 = 1. 

 Cape St. Lucas, Lower California. 



Head depressed, covered with small keeled scales. Superciliaries 

 large, promiuent, ])ieceded by a small mar<iinal i)late; muzzle covered 

 above with nearly equal polygonal scales, slightly or not keeled. Ros- 

 tral plate low, in form a nearly equilateral triangle: nasals two, the 

 anterior in contact with the rostral; numerous small scales anterior 

 to the pit. Thirteen or lourteen sui)eri()r labials, the i)osterior small; 

 fourteen and fifteen inferior, the second, third, and fourth in contact with 

 the geneial. Two rows of smooth scales and the infraorbital circle sep- 

 arate the labials from the orbit ; the scales of the former continue smooth 

 upon the temporal region, and are larger than the labials. Scales of the 

 body rounded, short upon the sides, especially those of the first three 

 rows, which, near the middle of the body, are not at all, or scarcely, 



