REPTILIA 



3^S 



to thirty-four young, each one twenty-seven inches in length and an 

 inch in diameter. (Figure 172.) 



The common boa {Boa constrictor) reaches a length not greater 

 than II feet. It is a native of tropical South America. Easily 

 tamed it is used by " snake-charmers," although its smaller size 

 renders it less thrilling to audiences, fearful lest they miss the sight 

 of a snake tightening its coils on its tamer. Ditmars relates a case 

 of a brood of 64 young. Other boas include the vicious Cuban boa, 

 the common American rubber boa, and the Indian sand boas. The 



Fig. 173. Thamnophis marciana. (Courtesy of A. G. Ruthven.) 



brown sand boa or two-headed snake {Eryx johnii) has a round 

 stumpy tail, sometimes painted with " eyes " by the Hindoos, who 

 claim that one end of the animal watches while the other sleeps. 



The sub-family Colubrinae includes the majority of snakes. 

 All of this family lack poison glands and hollow fangs. (Figure 

 173.) The Eastern ribbon snake is a beautiful reptile, reaching a 

 length of 3 feet. It feeds on fishes and amphibians. The garter 

 snakes {Eutania) are all prolific viviparous forms, and are beneficial 

 for the most part. The water snakes iTropidonotus) are sometimes 

 quite vicious but are non-venomous. The brown water snake is the 

 largest, reaching a length of 5 feet. An Indian water snake {T. 

 macrophthalmus) spreads its neck and was mistakenly brought in 

 by the natives when the British first offered a bounty for the hooded 

 cobra. The Indian rat snake of the Malay peninsula is protected 

 by a fine, as a rat exterminator. It reaches a length of 8 feet. The 

 American black snake {Zamenis constrictor) is not a constrictor, 

 but holds its prey to the ground under a coil. It destroys small 

 rodents, but occasionally eats amphibians and young birds. 



T\it family Colubridae include a number of large snakes killing 



