1847.] 



Indian Boa or Rock Snake. 



75 



ed by them. This remains to be proved by ocular demonstration, for 

 though perfectly possible and far from improbable, few would believe 

 it without unimpeachable evidence. 



When first examining one of the large reptiles the question natu„ 

 rally arises, how does it attack its prey, and when seized how is it 

 possible to swallow it through so small an aperture as its mouth. A 

 little further examination soon explains the difficulty, but as I do not 

 suppose every one has the same opportunities I have had, and if so 

 the inclination, I shall endeavour in a few words to show how beauti. 

 fully nature adopts the structure of her ever varying forms for the 

 position in which they are placed and to answer the ends for which 

 they are created. On the first view the Python seems a heavy, thick 

 though powerful snake, its body seemingly less rounded than the 

 more active and graceful serpents. Its belly is cased in broad-flat 

 uniform scales of a hard enamelled texture, the breadth of the body 

 being their greatest length. These scutoe form in this as indeed in 

 nearly all snakes the organs of locomotion. Its head is flattened and 

 its jaws are armed with two rows of strong teeth, bent backwards ; 

 these when once buried in the flesh act like hooks and prevent any 

 animal from withdrawing itself as long as the jaws remain closed ; 

 the vertibral column is so constructed that from the middle of each 

 vertebra on both sides a rib articulates, so loosely, that the most per- 

 fect flexibility is retained ; the lower ends of each pair of ribs are 

 joined to the inner surface of the abdominal scales and can through cer- 

 tain muscles be moved forward by pairs ; as each pair is moved the 

 scale to which it is joined does the same and this being pressed upon 

 the ground, the sharp posterior edge takes hold of the surface, — 

 and so on with them all. This principle of progression may be best 

 seen when a snake is ascending the steps of a stair, each scale in its 

 turn being then easily observed to catch upon the sharp angle of the 

 step and form a point from which the next is moved. As far as I have 

 been able to observe the Python is sluggish in its habits and prefers 

 lying in wait for its prey. The smaller ones feed upon frogs,— 

 small mammalia, such as rats, mice, &c. and also birds, principally 

 partridges and quails, these living mostly on the ground. The hrger 

 ones that are found in the jungle lie concealed from view by some 

 bush or long grass, and when lying motionless resemble the trunk of 

 a tree or bit of stone, so closely, that the eye is frequently deceived as to 

 the object. They adopt this method of lying in wait from the com- 

 i^arative slowness of their progressive motion, their niuccular poWviB 



