CHAPTER XXXVIIl: THE RAINBOW SNAKES 



Large mid Brillianily Coloured, Burrowing Serpents, of the Genera 

 ADASTOR and FARANCIA 



Alleged to be related to the tiny Worm Snsike (Carphophis), 

 the Rainbow Snakes are, from all external appearances, strikingly 

 different from their small ally. They grow to a large size — five 

 or six feet — and their handsome colouration is not eclipsed by 

 any- other North American reptile; intensifying the brilliant 

 pattern, is the opalescent lustre of the scales. 



With ail their beauty of colouration these serpents are degen- 

 erate burrowers and seldom show themselves above the ground. 

 The body is stout and powerful, but tapers gradually to a more 

 slender neck and a head that is small, flat and not distinct. The 

 eyes, placed well forward toward the snout, incline upward; 

 they are dull and have a minute pupil, like a pin-hole. In pro- 

 portion to the size, the tongue is exceedingly small. 



By a single character, technically considered an important 

 one, the Rainbow Snakes are divided into two genera. This is 

 the structure of the plate or plates following the nose 

 shield or rostral. With Abastor, there is a pair of these plates — 

 internasals. Farancia has a single iniernasal plate. In every 

 other way these snakes are similar. The teeth of the upper jaw 

 are of about equal size. There is no preocular plate, the loreal 

 plate forming a portion of the front border of the eye. The scales 

 are smooth and in 19 rows; ventral plate divided. Both Abastor 

 and Farancia, represented by single species, are confined to the 

 southern United States; both are most abundant in Florida. 



Following is a condensed formula to aid in identification: 



A. Two internasal plates. Genus Abastor. 



Blue-black, with three reddish stripes above. 

 Abdomen red, with rows of black spots. 



RAINBOW SNAKE, A. erythrograntmus. 



B. One internasal plate. Genus Farancia. 



Blue-black; upright, vermilion bars on sides. Abdomen 

 vermilion. red-bellied snake, F. abacura. 



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