298 Mr. J. J. Quelch on the 



constrictors, rudiments of hind limbs are found in the form of 

 claws, one on each side of the vent. 



These snakes are aquatic, and frequent especially the grassy 

 and sheltered banks in the still reaches of the streams and the 

 wide open water-savannahs. They are widely distributed in 

 all such places over the colony, and are abundant in all the 

 coast districts, more especially in the sheltered waterways 

 close to settlements in the country where poultry is reared. 

 Small specimens up to about 10 feet in length are very fre- 

 quently caught in such shallow waters, and larger specimens 

 are met with occasionally lying on the grass or tree-stumps 

 by the waterside, or in the act of constricting or swallowing 

 their prey, when they seem, as a rule, altogether disinclined 

 to move, except so far as the contortion of their body for 

 swallowing is concerned. 



It is mentioned, on apparently good evidence, that after 

 having swallowed an animal of large size these creatures lie 

 torpid, and are incapable of escaping if disturbed ; but to the 

 writer's knowledge no such case has ever been met with in 

 the colony, and it may be doubted whether snakes that were 

 big enough to take in large animals would be afterwards 

 incapable of movement, the more especially that they are 

 little likely to be far away from the moist bank of some 

 waterway. 



From the habitat of these reptiles it is not difficult to see 

 that they are well situated for securing their food. From the 

 abundance of creatures that slake their thirst by the waterside, 

 the boas are able to secure all that they need, and they cer- 

 tainly make good use of their opportunities, for when caught 

 they are always well-nourished and fat. Rodents and birds 

 seem to be favourite articles of diet, not only with this 

 species, but with the generality, if not all, of the constricting 

 snakes. 



The part which these and kindred reptiles play in main- 

 taining the balance of nature in a group of such remarkable 

 fecundity as the rodents must be therefore of considerable 

 importance to man in the tropics, the more so that the greater 

 number of rodents are among the most serious depredators on 

 cultivation in general. 



It must be stated, however, that the range of food of the 

 boas includes a great variety of other animals, such as the 

 great Salempenta or Teguexin lizards and the alligators, 

 besides the smaller mammals generally, and even the small 

 wood-deer and the peccary. The securing of prey such as 

 the mammals or birds is ordinarily an operation of short 

 duration, since the highly organized animal, being once en- 



