CYLINDER-SNAKES. 



J 95 



of their cage. The Indian species is frequently carried about by snake-charmers, 



who are in the habit of mutilating the short tail so as to make it look like a 



head ; whence arises the legend of two-headed snakes. A second Indian species 



(E. conicus) was formerly referred to a'separate genus (Gongylophis), on account 



of having a series of keeled scales between the eyes. 



Of the remaining members of the family, Lichanura, with one 

 Allied Genera. . . . .7™ 



Californian species, differs from the sand-snakes by the smaller size 



of the rostral shield, which is longer than wide; while Charina, which is likewise 



Californian, has the head covered with large shields. On the other hand, Bolieria, 



as represented by a single species from Round Island, near Mauritius, differs from 



all the other members of the group in having three or four keels on the scales, the 



muzzle being covered with large shields. 



Extinct Python- In this place may be noticed certain gigantic snakes from the 



like Snakes, lower and middle Eocene rocks of Europe, described under the name 



of Palcwphis, and represented by closely allied, if not generieally identical forms 



in the corresponding strata of North America. Equal in size to those of the largest 



pythons, the vertebrae differ from the latter (shown in the figure on p. 18) by the 



much greater height of the upper or neural spine, which has not the backwardly- 



directed process at its summit characterising the pythons. From the shape of 



these vertebra?, it is pretty certain that these snakes had compressed bodies like 



the modern sea-snakes, while from the nature of the deposits in which their remains 



occur, there can be little doubt that they were marine in their habits. Whether 



they were really allied to the pythons and boas may be doubtful, but in any case 



it is probable that they indicate a separate family. 



The Cylinder-Snakes. 



Family ILYSIIDJE. 



Agreeing with the pythons and boas in the retention of vestiges of the hind- 

 limbs, the small group of cylinder-snakes appears to form a connecting link 

 between the two former and the under-mentioned family of shield-tailed snakes ; 

 their essential point of distinction from the preceding being that the supra- 

 temporal bone of the skull is of small size, and included in the walls of the brain- 

 case, instead of standing out as a support for the. quadrate-bone, which is much 

 shorter than in the boas and pythons. Teeth are present on the palate as well as 

 in the jaws ; and the vestiges of the hind-limb usually take the form of a spur on 

 each side of the vent. In general appearance, and in the arrangement of the 

 scaling, these snakes approximate to the boas; while as regards the structure of the 

 skull they are intermediate between them and the next family. The distribution 

 of the group is remarkable, being restricted to Ceylon and South-Eastern Asia in 

 the Eastern, and to Tropical America in the Western Hemisphere. Three genera, 

 of which two have one species, while the third has three, represent the family. 

 coral Cylinder- The single representative of the typical genus of the family is 



Snake. y ie beautiful coral cylinder-snake (Rysia scytale), inhabiting the 

 Guianas and Upper Amazonia, and attaining a length of something over 2.1 feet. 



