SHIELD-TAILS. 



197 



The Shield-Tails. 

 Family JjROPELTlD^E. 



The snakes of this family, while agreeing with the boas and pythons in the 

 structure of the lower jaw, are sharply distinguished by the loss of all traces of the 

 limbs, and likewise by the complete disappearance of the supratemporal bone in 

 the skull. By Mr. Boulenger they are regarded as directly descended from the 

 preceding family of the suborder. The skull is remarkable for the firm union of 

 its constituent bones ; and although both jaws are toothed, the teeth are small and 

 feeble, and very rarely present on the palate. Externally these snakes are charac- 

 terised by their cylindrical bodies ; short, narrow heads, which pass imperceptibly 

 into the neck ; and by the 

 extremely short, truncated, or 

 slightly tapering tail, which 

 generally ends in a rough, 

 naked disc, although in one 

 genus it is covered with keeled 

 scales. On the body the scales 

 are small and polished, those 

 on the lower surface being 

 always somewhat larger than 

 those above ; the eye is minute, 

 and the cleft of the mouth 

 comparatively small, and in- 

 capable of much dilatation. 



These snakes are repre- 

 sented by upwards of seven 

 genera, some of which com- 

 prise a large number of species, 



and are restricted to Ceylon and the mountains of Peninsular India. They are 

 purely burrowing creatures, generally living in soft earth, at a depth of several 

 feet, and consequently but seldom seen unless specially searched for. They are 

 frequently dug up in the cultivation of tea and coffee plantations, and may be 

 found beneath logs and stones. On the mountains these earth -snakes, as they 

 are frequently called, may be met with in the open grass-lands ; and during the 

 rainy season they not unfrequently leave their burrows to travel some distance 

 on the surface. Of relatively small size, many of them are beautifully coloured 

 with red and yellow, while those that are black display an iridescence like that 

 of some of the smooth-scaled skinks among the lizards. The food of these reptiles 

 appears to consist solely of earth-worms ; and the eggs are hatched before quitting 

 the body of the parent. There is a legend current among the natives of India to 

 the effect that every time a cobra bites it loses a joint of its tail, and eventually 

 acquires a head like that of a toad ; and Sir J. E. Tennent was of opinion that 

 this fable was based on the shield-tailed snakes, in which the jaws have lost the 

 great power of dilatation so characteristic of serpents in general. 



A SHIELD-TAILED SNAKE. 



