174 BEPTILBS. 



ff. Snout not recurved and keeled ; species of large size. 

 g. Gastrosteges 130 to 155 ; general color 3 series of dark 

 blotches on a lighter ground, sometimes simply 

 barred or uniformly dark or reddish ; aquatic. 



TROPIDONOTUS, 2. 



gg. Gastrosteges 200 to 235 ; general color brown or black, 

 sometimes with quadrate blotches ; abdomen usually 

 blotched ; terrestrial. . . . COLUBER, 8. 

 ** Dorsal scales smooth. 



\ Anal plate entire ; gastrosteges 175 to 200 color black, brown 



or red, more or less variegated. 

 h. Rows of scales 21 to 25 ; loral plate present. 



OPHIBOLUS, 12. 



hh. Rows of scales 19 ; no loral plate. . . OSCEOLA, 13. 

 \\ Anal plate bifid ; scales in 13 to 17 rows. 

 i. Gastrosteges 170 to 210 ; scales in 17 rows ; snakes very 

 large or very long ours lustrous pitch black in color 



when adult BASCANITJM. 6. 



it. Gastrosteges less than 170 ; snakes of medium to small size. 

 j. Scales in 13 rows ; gastrosteges 120 to 135 ; brown, salmon 

 color or yellowish beneath. . CARPHOPHIOPS, 18. 

 jj. Scales in 15 to 17 rows. 



k. Color black, unstriped ; a distinct yellowish ring about 



neck"; gastrosteges 140 to 160. . DPADOPHIS, 11. 



kk. Color clear bright green ; no collar ; gastrosteges 130 



to 140 LIOPELTIS, 10. 



kkk. Color brownish, with black dots ; no collar ; gastro- 

 steges 115 to 125 VIRGINIA, 17. 



\\\ Anal plate bifid ; scales in 19 rows ; gastrosteges, 170 to 185. 

 I. Bluish black with squarish red spots on the blanks ; abdomen 



red with black spots FARANCIA, 14. 



U. Blue-black, with three red lines ; abdomen yellowish with 

 a series of dark spots ABASTOR, 15. 



/. HETERODON, Beauvais. SPREADING ADDERS. 

 1. Jf. platyrhinuSf Latreille. BLOWING VIPEB. HOG- 



