8 CROTALOIDEA. 



4. The gland that secretes the poison is situated near the eye, under the temporal 



muscle, so as to be compressed by its contraction. The poison varies in 

 intensity perhaps in the different genera, but more so according to the state 

 of the animal. It is most active in the healthy snake — in the summer season 

 — when it has been long retained — when the animal is greatly irritated, &c. 

 «Szc. To be deadly, however, it must be introduced into the circulation, for 

 it can be taken into the stomach with mipunity. 



5. These serpents are all viviparous; or, the egg is retained in the female until it 



is hatched, and the young annual is then expelled alive. 



