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and elongate, with rough points, and the young fight, strike and 

 defend themselves as soon as their heads are out of the shell. They 

 cut their way through by means of an egg-tooth projecting from 

 the middle of the upper snout, having for its function the slitting 

 of the leathery shell through which the animal crawls, after which 

 the egg-tooth is shed. 



Fig-. 14. — Diagram showing the percentages of Food 

 Items of Black Snake {Base anion constrictor): 25 

 per cent. Insects; 15 per cent. Snakes; 22 per cent. 

 Field Mice; 8 per cent. Birds' Eggs; 4 per cent. 

 Rabbits; 4 per cent. Voles; 7% per cent. Frogs; 4 

 per cent. Birds; 7 per cent. Mammals (unidentified); 

 3% per cent (Cither on ia i-egaiis). Larvse of Royal 

 Moth. 



Writers have reported the Black Snake as feeding upon a great 

 variety of substances as follows: Small mammals (Atkinson), mice 

 and rats (Shaw and Cuvier), field mice (Garman and Smith), squir- 

 rels and opossums (Cuvier), small quadrupeds (DeKay), milk, in 

 pans (Shaw), birds (DeKay, Garman, Smith, Cuvier, Atkinson and 

 Harlan), eggs (Shaw, DeKay, Morse and Harlan), lizards (Cuvier), 

 rattle snakes (Shaw), batrachians (Atkinson), toads (DeKay), frogs 

 (DeKay, Garman, Smith and Cuvier), and insects (Morse). Very few 

 persons have published anything definite as to the species of these 

 various animals upon which they feed. Dr. Atkinson, of Carnegie 

 Museum, has taken weasels and voles from their stomachs, but as 

 a rule specific statements of their food have not been given by 

 other writers. Our investigations show the following list of food 

 for different individuals of this species: 



