THE COLUBRINE SNAKES 2577 



lip and edges of the jaws alone preserving the original yellowish green. The 

 scales are arranged in twelve rows, and are mostly smooth, although the two middle 

 rows on the back are keeled, the eye being of very large size. Next to the coral 

 snake, the sipo is the most abundant of Brazilian ophidians, and may be met 

 with both on sandy jungle-clad ground close to the shore at Rio de Janeiro and 

 Cape Frio, where specimens of upward of ten feet in length have been observed. 

 In addition to sandy localities it also frequents swampy spots near the sea. In its 

 movements it is so rapid that, when startled, it seems to disappear like a flash of 

 lightning. It feeds largely upon frogs, as well as upon lizards and young birds, 

 and lays only five eggs, which are remarkable for their cylindrical and slender form. 

 In the Old World and Australia the wood snakes are replaced by 

 the solid-toothed tree snakes, forming the genera Dendrophis and Den- 

 drelaphis, both of which are distinguished from all the preceding types by having 

 the hinder border of each of the shields on the lower surface of the body with a 

 notch on each side, corresponding to a suture-like lateral keel; the scales of the body 

 being arranged in from thirteen to fifteen rows. While in the first named of the 

 two genera all the teeth in the hinder upper jawbone are approximately equal in 

 length, and the row of scales in the middle line of the back larger than the others, 

 in the second genus the foremost teeth in the hinder upper jawbone are enlarged, 

 but the middle row of scales on the back are similar to the rest. All these snakes 

 have large eyes, and elongated and often compressed bodies, and their general col- 

 oration is some shade of green or olive, often with a bronzy tinge; their habits be- 

 ing mostly arboreal. Of Dendrophis nine species are known ranging from India to 

 Australia, while Dendrelaphis is represented by five species ranging from India and 

 the Malayan region to the Philippines. 



The last representative of the solid-toothed series of the Colubrines 

 'citinfir 



, that we have space to mention is the curious little egg-eating snake 



(Dasypeltis scabra] of South Africa which represents a subfamily 

 {Dasypeltincz) by itself. The essential characteristic of the subfamily is the rudi- 

 mental condition of the dentition, the front of both the lower jaw and upper jaw 

 being devoid of teeth. To compensate for this lack of ordinary teeth, the egg- 

 eating snake is, however, provided with a series of about thirty of what may be 

 termed throat teeth, these being the lower spines of the vertebrae, which project 

 into the oesophagus, and are tipped with enamel. The scales are strongl)' keeled. 

 This little snake is about a couple of feet in length, and has a body not much 

 thicker than a man's finger. Although it lives in trees, and feeds on the eggs of 

 small birds, it will when pressed by hunger descend to the ground and rob hens' 

 nests. That such a tiny creature should be able to swallow a hen's egg seems in- 

 credible, but nevertheless a specimen has been taken with the egg actually within 

 its jaws, and the whole head so swollen as to render the mouth incapable of being 

 closed; while an example in the L,ondon Zoological Gardens swallowed pigeons' 

 eggs without any apparent difficulty. When swallowed, the egg is split longitudi- 

 nally by the row of teeth in the throat, and the whole of the contents secured. After 

 being thus broken, the two halves of the shell, generally fitted into one another, 

 are rejected. 

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