13. COLUBRIDJE 6+S 



e'. — Rostral turned up at tipj scales in 17 rows. 

 Ficimia. — p. 777. 

 c. — Loreal plate present, 

 dd. — Pupil round, 

 ee. — Rostral not free at edges, 

 ff. — Normally one anterior temporal j urosteges 

 fewer than 75; scales in 15 or 17 rows, 

 g. — No narrow light transverse nuchal collar; 

 fourth infralabial usually largest; preocular 

 normally single and temporals 1+2. 

 h. — Snout more or less depressed; each gastro- 

 stege not marked with a transverse blackish 

 bar. 



Sonora. — p. 8 5 8. 

 h'. — Snout high ; each gastrostege with a narrow 

 transverse blackish bar. 



Contia. — p. 770. 

 g'. — A narrow light transverse nuchal collar; 

 fifth infralabial usually largest; preoculars 

 normally two, and temporals 1 + 1 . 



Diadophis. — p. 647. 

 ff. — Anterior temporals normally more than one; 

 urosteges more than 75; scales in 15 or more 

 rows; no single narrow nuchal collar, 

 gg. — Scales in fewer than 23 rows; gastrosteges 

 fewer than 240. 



Coluber.— p. 65 8. 

 gg'. — Scales in more than 30 rows; gastrosteges 

 more than 240. 



Elaphe.— p.697. 

 ee'. — Rostral large, with free lateral edges; colora- 

 tion in longitudinal bands. 



Salvadora.— p. 688. 

 dd'. — ^Pupil vertically elliptical. 



