THE PYTHONS AND BOAS 



2543 



illse or anterior upper jawbones, and also in generally having two rows of shields on 

 the under surface of the tail, the pythons are specially characterized by the dis- 

 tinctly prehensile tail, and likewise by the presence of deep pits in the rostral and 

 anterior upper labial shields of the head. As minor characteristics, it may be men- 

 tioned that the teeth, none of which are grooved, gradually decrease in size from 

 the front to the back of the jaws; while the eye is of moderate size, with a vertical 

 pupil. The head is distinct from the neck, and has the extremity of the snout cov- 

 ered with large shields, while its hinder portion may be overlain either with sym- 



INDIAN PYTHON CRUSHING ITS PREY. 

 (One-tenth natural size.) 



metrical shields, or with small scales; and each nostril is placed in a half-divided 

 nasal shield, separated from its fellow on the opposite side by a pair of internasal 

 shields. The body in these snakes is more or less compressed, while the scales on 

 the upper surface and sides are small and smooth; and the prehensile tail is of mod- 

 erate length, or short, with the whole or greater part of the inferior shields arranged 

 in two rows. 



Pythons, or, as they are frequently termed, rock snakes, are repre- 



L j u -ijo^iAr- 



sen ^ e " by nine species, and range over tropical and South Africa, 



Southeastern Asia, and Australasia. With the exception of the 

 American anaconda, some of the pythons are the largest of all snakes, and although 



Distribution 

 d H vt 



