P. Reptiles of Massachusetts. 39 
# i 
gain more than one rattle in a year, and to lose in 
proportion, the exact number being regulated no 
doubt by the state of the animal as to health, nour- 
ishment, liberty, &c. I have known two rattles 
added in one year, and Dr. Backman has observed 
four produced in the same length of time." 
The power of fascination attributed to this genus, 
is too absurd to require our serious consideration. 
