i88 SNAKES. 



the smooth scales of the body ; by the presence of shields on the head ; and by the 

 labial shields being either devoid of pits or with only shallow ones. In form 

 the body is more or less compressed, and the tail either moderate or long ; while 

 the eye is of medium size with a vertical pupil ; and the shields on the head may 

 be either small and irregular, or large and symmetrical. 



These snakes are represented by nine species, the largest of which is the pale- 



DOG-HEADED TREE-BOA (J liat. size). 



headed tree-boa (Epicrates angulifer) of Cuba, attaining a length of about 7 feet ; 

 another well-known species being the streaked tree-boa (E. striatus), from San 

 Domingo and the Bahamas. The thick-necked tree-boa (E. cenchris), must, 

 however, be mentioned, its habitat ranging from Costa Rica to the northern 

 districts of Peru and Brazil. The figured species, which attains a length of about 

 5 feet, is either pale brown above with dark olive-brown spots separated by 

 narrow intervals from one another, or brown with wavy or zigzag yellowish 

 crossbands, not unfrequently margined with blackish brown. Each side of the 



