208 



SNAKES. 



this well-known species extends from India to Java. Common everywhere in 

 India, and feeding on mammals, birds, and frogs, the rat-snake derives its name 

 from its habit of entering houses in search of rats and mice. Like its allies, it is 

 fierce and always ready to bite ; and old specimens brought to Europe never become 

 tame. When irritated, it utters a peculiar sound, which has been compared to that 

 produced by gently striking a tuning-fork. A smaller allied Indian species (Z. 

 corrus) differs by having the scales arranged in fifteen, instead of seventeen rows. 



Nearly allied to the preceding are the American running snakes, 

 of which the pantherine snake (Ptyas pantherinus) is a familiar 

 and handsome example. From the last genus the running snakes are chiefly 



Running Snakes. 



BLACK-MARKED AND HORSESHOE SNAKES (J nat. size). 



distinguished by their teeth and the larger size of the eyes. They are all large 

 and powerful reptiles, with cylindrical body, clearly defined head, large eyes, 

 regularly tapering tail, which is at least equal to a fourth of the total length, the 

 scales smooth and arranged in from fifteen to seventeen rows, normally-arranged 

 head-shields, unkeeled inferior shields, and about twenty-one equal-sized teeth in 

 the hinder upper jawbone. The pantherine snake, which is an inhabitant of the 

 hottest regions of the Guianas and Eastern Brazil, and is especially common in the 

 neighbourhood of Rio de Janeiro, is characterised by having fifteen rows of scales 

 on the body, the lack of the small lower preorbital shield, and its general form and 

 coloration ; its length being as much as 7 feet. The ground-colour is yellowish 

 grey on the upper-parts ; on the front of the head are three dark crossbars, while 

 two broad longitudinal stripes run along the hinder part of the head and neck ; 



