220 Zoologica: N. Y. Zoological Society [I; 11 



Zamenis and the like must be fed at intervals of four to six days, or 

 they soon exhibit emaciation. 



The large and important genus Coluber made up of New and Old 

 World species, is composed of snakes of considerable economic value. 

 Several important and useful species inhabit the southeastern por- 

 tion of the United States, where are to be found the Black Coluber, 

 C. obsoletus, the Four-Lined Coluber, C. o. quadrivittatus, the €^ray 

 Coluber, C. o. confinis, and the Corn Snakes, C. guttatus. All of 

 these snakes feed upon rats and mice, although their food also con- 

 sists of birds. Their depredations among the birds, however, are quite 

 counterbalanced by their useful work in destroying the small mam- 

 mals that are a menace to grain and other products of the agricul- 

 turist. With the great majority of the species of Coluber there is a 

 decided tendency to feed exclusively upon warm-blooded prey. The 

 writer has had under observation a generous proportion of the species 

 of this genus, both the European and Anierican, and in his continuous 

 studies covering a period of over fifteen years, has not induced one 

 of these snakes to feed upon any type of batrachian. Very rarely, 

 these snakes have been noted to feed upon lizards, although they 

 seldom or never exhibit a cannibalistic tendency common among the 

 serpents of the other genera under immediate consideration. Sum- 

 ming up the feeding habits of the genus it is appropriate to describe 

 these powerful constrictors, as snakes of economic importance that 

 feed almost entirely upon mammals and birds. Pituophis, an Amer- 

 ican genus of large and powerful constrictors, embraces quite similar 

 habits, and one species in particular, the Bull Snake, Pituophis sayi, 

 is a reptile of such great economic value throughout its habitat, that 

 it might be introduced and protected in the great grain belts of the 

 United States, as a common enemy to the several species of highly 

 destructive ground squirrels or spermophiles. 



Of apparent relationship to the genera considered in the preced- 

 ing paragraph, the writer quotes Herpetodryas and Dendrophis, that 

 have assumed marked arboreal habits, with a consequent change of 

 food. With Herpetodryas we note the interesting trait of a fondness 

 for birds, which are readily captured in the low bushes or trees 

 inhabits, and also a liking for frogs and fish. Several members of 

 this genus apparently waver in the development of their mode of 

 living, between an arboreal life and a semi-aquatic existence. They 

 often dive from the trees into the water in seeking amphibious prey, 

 but the writer has not induced any species of this genus to feed upon 



