SERPENTS. 365 



In the family Colubkidje have been placed the greater number of non-veno- 

 mous ophidians which do not present any striking characters either as to their habits or 

 structure ; a description must therefore be general. Body of moderate length and 

 breadth ; head well-ijroportioned and separated from the body by a more or less con- 

 stricted neck; eyes and mouth of moderate size; teeth covering both jaws and palate, 

 and never presenting any special development ; the plates of the head are evenly 

 arranged, and those of the body never present any outline or structure deviating 

 greatly from the normal. So few prominent structural variations are presented by the 

 several forms, that grouping from this standpoint is difficult and, at best, unsatisfactory. 

 Some naturalists have endeavored to base an arrangement on habits. Yet, as many 

 forms are intermediate, and others unite the habits of evidently widely separated 

 groups, this plan is even more unsatisfactory than the first. The family is cosmopoli- 

 tan, its members being found in nearly every country under the tropical and temperate 

 sun. Australia and some of the Pacific islands, however, are not represented. North 

 America has a large number of forms, included in several genera, the distinctive 

 features of which are chiefly based on the arrangement of the cervical plates. 



The introductory genus is Cydophis, which is represented by one of the most 

 beautiful, as it is one of the most familiar, reptiles, the green-snake, Cydophis vernalis. 

 This is a most gentle and harmless ophidian, allowing itself to be handled in the 

 roughest way, and seldom offering the least opposition. Specimens are often captured 

 and made pets of, living in confinement for considerable periods of time. In nature 

 they are found in moist meadow-lands, where they are concealed by their protective 

 color, and where they find an abundance of insect life well suited for their food. The 

 green-snake is not only found on the ground, however, but is an active climber, and 

 may not infrequently be seen entwined among the branches of bushes or of low trees. 

 The genus is represented in India by a much larger form, C. major, which sometimes 

 exceeds three feet in length. 



Closely related to Cydophis is the genus Jlerpetodryas, representatives of which 

 are found in both hemispheres. They are elongated forms, adapted to an arboreal 

 life, their colors, shades of green and brown, being well adapted to conceal them. 

 JI. carinatits is found in Brazil and Surinam, and is peculiar in that it has no vertebral 

 row of scales, the several series of the body always being in an even number. 



The genus Coluber has many interesting forms, native as well as exotic. The 

 Alleghanian variety of C. obsoletus, the mountain black-snake, has received considera- 

 ble attention, from its distribution. It was first detected in New England, along the 

 Connecticut valley, where it attracted attention as a black-snake having the scales 

 keeled, the ordinary Bascanium con,s<?-«c<or having the scales smooth, and though since 

 found in other eastern localities, its proper home is among the mountains of the Appala- 

 chian range, where it sometimes reaches a length of seven feet. In confinement its tem- 

 perament is quite different from that of its smooth-scaled cousin, being mild and gentle. 

 G. guttatus, the corn-snake, inhabits the southeastern part of the United States, and was 

 first described, in 1743, by Catesby, as follows : " It is all over beautifully marked with 

 red and white, which seems to have given it the name of corn-snake, there being some 

 maize or Indian corn much resembling this in color; they are robbers of hen-roosts, 

 otherwise they are harmless." In its habits the present form differs from the majority 

 of our common snakes in being crepuscular, spending the day hid away in some 

 crevice. In length the corn-snake sometimes reaches five feet. This form has been a 

 great stumbling block to herpetologists, having been described under a dozen different 



