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 by coiling its lengthy body round tlieir chest, and 

 then by strong muscular contraction, compressing the ribs so firmly 

 that respiration is prevented, and the animal so seized speedily 

 perishes from suifocation. But having succeeded in extinguishing 

 life, the most difficult task still remains to be accomplislied. How 



Fig. 318.— boa cox&TBicroR watching for 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? 

 The mode adopted is as follows : — Having relaxed the dreadful 

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



