218 Zoological N . Y . Zoological Society [I; H 



Asia, and Zamenis, the latter with twenty-eight species inhabiting 

 the New and the Old world and haying among its representatives, 

 our familiar black snake, we note the characteristic of semi-constric- 

 tion. The species are omnivorous as regards the feeding habits of 

 serpents, as they prey upon small mammals, birds, other reptiles 

 (serpents and lizards) and amphibians, although the writer has never 

 been able to induce a serpent of either of these genera to feed 

 upon earthworms. 



Zamenis: — ^Among the species of this genus are several North 

 American snakes that must be rated as of economic value. While 

 they prey to a certain extent upon amphibians, they only occasionally 

 feed upon frogs. They seldom or never attack those amphibians 

 with granular skins, like the toads, and several species of the more 

 terrestrial frogs; hence we might eliminate from their diet, those 

 species of amphibians which are particularly beneficial to the agri- 

 culturist. Of slender form, and very active, they hunt for rodents 

 within their burrows, destroying the young and pursuing the adults. 



Well-known Old World species of Zamenis are the Indian Rat 

 Snakes, Z. korros and Z. mucosus. Familiar New World types are 

 the Black Snake, Z. constrictor and the Whip Snake, Z. flagelliforme. 

 Both frequent rather open places, being partial to the edges 

 of meadows where they hunt their prey in the neighboring brush or 

 in stone walls. Here they feed largely upon the smaller rodents, 

 which tend to damage the products of the farmer. 



From his studies of the separate species of Zamenis in captivity, 

 the writer has noted that the Black Snake evinces a preference for 

 the smaller rodents. It will also eat birds and the various species 

 of smaller snakes, although it does not attack the poisonous snakes as 

 has often been alleged. The writer has noted it feeding upon individ- 

 uals of its own species, and the closely related whip snake. It will 

 take lizards and is exceedingly active in catching these. Frogs are 

 also eaten, but among these are several species that the snake will 

 grasp and immediately reject. An example of this type of batrachian 

 is Rana palustris, which exudes an irritating secretion [from the 

 skin. Toads are never eaten, and there is a disinclination to feed 

 upon the tailed batrachians, owing possibly to their irritating skin 

 secretions, although many small snakes feed upon them. 



Z. flagelliforme, the Whip Snake, is of rather different feeding 

 habits. It is particularly fond of small rodents and birds, occasion- 



