Snakes and Frogs and Their Relatives 



[203 



The rattle is made up of a series of horny sections or "buttons" 

 on the end of the spinal column. They are loosely interlocked, 

 and when the snake vibrates its tail they click against each other. 

 Many other kinds of snakes also vibrate their tails, and if they 

 happen to be lying among dead leaves the resulting rustle sounds 

 like a rattle. However, the rattlesnake's vibration is distinctive. 

 It is a half metallic, half insect-like sound, somewhat like the 

 dull buzz of the bumblebee. 



THE RATTLE RINGS 



At birth a rattler has a bulbous swelling at the tip of its 

 tail. When the snake molts, the tip of its old skin cannot be 

 pulled over this enlargement, so it remains and forms the begin- 

 ning of a rattle. As successive molts take place, the tip of the 

 skin that cannot be shed forms an additional segment or ring. 

 The rings form around a bone known as the ''shaker," made up 

 of the last seven or eight vertebrae which fuse together soon after 

 the snake is born. 



THE DANGEROUS DIAMOND-BACK RATTLER 



The diamond-back, so called because of the distinctive diamond-shaped pattern on 

 its back, is one of the relatively few harmful snakes in the United States. Prac- 

 tically all the deaths by snake bite in this country (estimated at about a hundred a 

 year) are caused by diamond-back rattlers, prairie and timber rattlers, and water 

 moccasins. If proper treatment is given, their bites rarely prove fatal. 



