386 



SERPENTS. 



On its approach, the Boa darts upon its prey and more swiftly than 

 the eye can follow, encircles it in voluminous folds. The Boa thus 

 kills its victims hy coiling its lengthy body round their chest, and 

 then hy strong muscular contraction, compressing the ribs so firmly 

 that respiration is prevented, and the animal so seized speedily 

 perishes from snifocation. But having succeeded in extinguishing 

 life, the most difficult tnsk still remains to be accomplished. How 



FlG. 318. BOA CONSTRICTOR WATCHING FOB PREY. 



is the serpent, utterly destitute as it is of all external limbs, to force 

 down its throat an animal many times thicker than its own body t 

 The mode adopted is as follows .-Having relaxed the dreadtu 

 embrace, it once more winds itself round the slain animal, and 



