The fact that in the African egg snake - Dasypel t is sea bra (L.) - 

 the lower aristate hypapophyses of the anterior vertebrae penetrate 

 the wall of the esophagus and serve for crushing in the center of the 

 shells of eggs, which comprise the basic, and often the only food of 

 this snake, has been known widely and early. It was worked on and 

 demonstrated in great detail at the end of the last century by L. 

 Katheriner, 1898 and recently by C. Gans, 1952. 



An analogous function of the hypapophyses is also assumed in the 

 furrow- backed snake Elachistodon westermanni Reinhardt which is known 

 only from a few specimens from N. Bengal (India and East Pakistan). 

 The ecology of this very rare species is entirely unknown. The con- 

 clusion that it is an egg-eating snake was based on the similarity of 

 its hypapophyses with those of the egg snake and on finding an egg yoke 

 in the stomach of one. However, undoubtedly, this snake must eat other 

 food also, consisting primarily of various small vertebrates. I note 

 that Gans and Williams (1954), having re-examined specimens kept in the 

 British Museum of Natural History, and parts of its skeleton, are agreed 

 that the hypapophyses perforate the wall of the esophagus. 



In these species of snake there are few teeth (in the egg snake, 

 for example, there are 5 - 9 on the maxilla, 4 - 5 on the dentary, where 

 they are situated only in its hind section, 4 - 8 on the palatine, and 

 none at all on the pterygoid, and they are so small that they do not 

 protrude from the mucous membrane. The reduction in the number and size 

 of the teeth, just as in a number of other peculiarities of skeletal 

 structure, is considered an adaptation f or swallowing eggs, which have a 

 firm shell, and, particularly, for regurgitating the latter from the 

 mouth in a crushed state. 



Some authors (Boulenger, 1894, etc.), considering the structural 

 peculiarities of the anterior hypapophyses, separate the monotypic genera 

 Dasypeltis and Elachistodon into special subfamilies of the family 

 Colubridae: the first into the Dasype 1 t inae , and the latter, in which 

 there are 1-2 grooved teeth in the hind section of the upper jaw, into 

 the Elachistodontinae. 



Along with these species of snakes, there exist also a number of 

 those which eat birds' eggs as well as small mammals, lizards and other 

 animals. However, in the past 40 years the adaptations for and mechanics 

 of crushing the firm lime shell of eggs have not been studied. I know 

 only of A. A. Emelyanov's indication (1929) of the fact that the Amurian 

 runner, climbing to a chicken- coop, eats chicken eggs, and, "having 

 swallowed the egg, it [the runner -- S. Ch.] bends it and breaks it in its 

 intestine." However, the latter, as can be expected, has not been con- 

 firmed in observations of the swallowing of eggs by this runner. 



