CROTALUS DURISSUS. 15 
Mr. Peale of the Philadelphia Museum, kept a living female Rattlesnake for 
fourteen years. It had, when it came into his possession, eleven rattles, several 
were lost annually, and new ones took their place; at its death, after fourteen 
years confinement, there were still but eleven joints, although it had increased 
four inches in length. It is thus evident that the growth of these appendages is 
irregular, and that the age of the animal cannot be determined from their number. 
The number of rattles vary much; the greatest I ever saw was twenty-one, all of 
which were perfect. 
