ixil . INTiloDucTid^f. 



genera Eutcvnia, IJ'erodia, Regina, and Sforeria, are Xortli American; Ileli- 

 cops and Hydrops are better represented in Central and South America. 



Although the family names in common use are retained here, they are 

 raidved as subfamilies of one great family, including all the Acacophidia 

 or Colubrine snakes, the Colubrkke. The fiimily Cohihrinw contains in the 

 genus Coluber several species very common in the United States: the Black 

 snake, C. constrictor, is found over a great portion of the continent, and tlie 

 section of the genus containing the Coach Whip snake (Masticoj/^iis), C. 

 flcujelUformis, includes half a dozen species, from the Southern States, Mex- 

 ico, and as far south as Chili. Two species of the South American genus 

 Spilotes are found in the Gulf States. Pityophis, Cyclophis, Phyllophilophis, 

 and Salvadora are North American. As the name Salvadora does not seem 

 to be used elsewhere in the animal kingdom, it has been retained. IJromi- 

 cus is South American and West Indian, but contains one species peculiar 

 to the Southeastern United States and several others found in Southern 

 Mexico. The old world genus Elaphis claims several widely distributed 

 species from the southern half of the continent. 



Tachymenis, Erythrolamprus, Liophis, and Xenodon are South American 

 CoroneUince, and are represented by a few species in the southern part of 

 Mexico. OphiboJus, Diadophis, Heterodon, Rhinocheilus, Cemdphora, and Hyji- 

 siglena ai'e classed as North American ; the first three are found in all 

 the States, with, perhaps, a few exceptions in the northern tier. 



The Calamarince, of the genera TantiUa, Contia, Sonora, Virginia, and 

 Carphophis are Northern; Ficimia, Cheilorhina, Stenorhina, JSfinia, Geophis, 

 and -Elapomorphus are shared by Mexico with South America. 



Tree snakes are found in the Dipsadince, Scytalince, Dendrophincf, a;nd 

 Cohibrince ; water snakes in the Natricince ; and ground snakes in the 

 Calamarince, Coronellince, and Colubrince. But in each family there are 

 species whose habits are so uncertain as to render their positions doubt- 

 fiU. 



TOXICOPHIDIA. 



Grouping all the venomous serpents in a single suborder, brings together 

 animals of considerable diversity. Because of their differences they have 

 been arranged in various sections : one, the Proteroglypha, in which the 

 fangs are erect, immovable, and grooved in front ; and another, the Solen- 

 oghjpha, which are distinguished by an erectile perforate fang. The Pro- 



