68 



HERPETOLOGY OF MICHIGAN. 



Po Pro 



Fig. 21. Head of snake, side view, to show arrangement of scales. 



P, prenasal; Po, postnasal; L, loreal; Pro, preocular; Poo, postoculars; T, first temporal; 

 T.2, second temporals; S, superior labials; I, Inferior labials. 



Fig. 22. Head of snake, side view, to show arrangemant of scales. 

 P, rostral; O, iuternasals; F, prefrontals; PR, frontal; I, supraocular; R, parietals. 



a 



Fig. 23. Scales on the body of a snake. (After Cope.) 

 V, ventrals; a, anal plate; s, subcaudals, d, dorsals. 



