428 APPLIED BIOLOGY 



kill animals by constricting. Most of the snakes of the 

 United States are not poisonous. Snake poisons are secreted 

 by glands in the upper lips, and the " poison fangs " are upper 

 teeth with grooves or tubes for conveying poison beneath 

 the skin of the victims. 



The remedies for snake bites are briefly as follows : 

 (1) Place tight ligature on arm or leg to prevent circula- 

 tion of blood; (2) enlarge by cutting the punctures made 

 by fangs in order to drain away as much poisoned blood as 

 possible; (3) wash out cuts with wine-colored solution of 

 potassium permanganate; (4) take very small doses of 

 alcoholic stimulants, enough to cause increased pulse-beats ; 

 larger doses are dangerous ; (5) consult a good surgeon, be- 

 cause blood poisoning may result from the wound, and also 

 it may be necessary to have stimulants and anti-venomous 

 serum injected hypodermically ; (6) keep wound covered 

 with a cloth or cotton wet with some antiseptic solution. 



Alligators and crocodiles are sometimes dangerous to man. 

 Their tough skin is used for leather. In their embryonic 

 development, all crocodiles, alligators, turtles, most snakes 

 and lizards are oviparous. Some snakes and lizards retain 

 the eggs in the oviducts until development is completed, 

 that is, they are viviparous. 



Important Groups of Living Reptiles 



Lacertilia lizards (iguana, Gila monster, horned toad, chameleons, 

 etc.). 



Ophidia snakes (vipers, python, boa, water-snakes, rattle-snakes, 

 etc.). 



Chelonia turtles (tortoises, terrapins, soft-shelled turtles, box- 

 turtles, etc.). 



Crocodilia crocodiles, alligators. 



Reading or reference for students: Dithmar's "The 

 Reptile Book." 



