252 DENIZENS OF THE DESERT 



since last they were used. Furthermore, I think 

 it shows good judgment to sleep off the ground 

 on a cot swinging from a tree if possible, as soon 

 as the warm nights begin. There is no use tak- 

 ing chances. 



There is abroad a colossally absurd notion 

 that rattlesnakes are always found in pairs, and 

 that if you kill one the other will soon seek its 

 mate. It is quite possible that during the spring 

 months, that is, the mating season, they may 

 occasionally be found near to one another, but 

 this pairing is only temporary and during the 

 remainder of the year individuals wander soli- 

 tarily. 



All rattlesnakes are ovoviviparous; that is, 

 they hatch their eggs before they are laid. The 

 egg, with its yolk, white, and thin, flexible, 

 membraneous shell, is formed within the ovi- 

 duct of the female, but it never leaves the body. 

 Hence the young are born alive. 



Crotalus cerastes, the horned rattlesnake, or 

 sidewinder, is the most characteristic snake of 

 the Lower Sonoran Desert areas of the Great 

 Basin — southeastern California to southern 

 Nevada, southwestern Utah and Arizona. In 



