ILLUSTRATIONS 



Figure I'age 



1 . The normal arrangement of head scales in Pituophis - 6 



2. Head of Pituophis melanoleucus melanoleucus 7 



3. Head of Pituophis sayi affinis 8 



4. Head of Pituophis catenifer deserticola 9 



5. Head of Pituophis deppei jani 10 



6. Dissected hemipenis of Pituophis sayi sayi 10 



7. Sexual variation in number of ventrals in 72 specimens of Pituophis e. 



catenifer 11 



8. Sexual variation in number of caudals in 72 specimens of Pituophis c. 



catenifer 12 



9. Sexual variation in ratio of tail length to total length in 72 specimens 



of Pituophis c. catenifer 13 



10. Typical method of reduction in number of scale rows throughout the 



genus Pituophis 15 



11. Color pattern of Pituophis deppei deppei 28 



12. Geographic variation in number of scale rows in Pituophis deppei 



deppei 30 



13. Geographic variation in number of ventrals in Pituophis deppei deppei, _ 31 



14. Geographic variation in number of caudals in Pituophis deppei deppei.- 32 



15. Geographic variation in number of ventrals plus caudals in Pituophis 



deppei deppei 33 



16. Geographic variation in number of dorsal spots on body in Pituophis 



deppei deppei 34 



17. Geographic variation in ratio of tail length to total length in Pituophis 



deppei deppei 35 



18. Distribution map of Pituophis deppei deppei, P. d. jani, P. lineaticollis, 



P. sayi sayi, and P. s. affinis 36 



19. Variation in number of scale rows in the forms of the deppei group 37 



20. Variation in ratio of tail length to total length in the forms of the 



deppei group 38 



21. Variation in number of ventrals in the forms of the deppei group 38 



22. Variation in number of caudals in the forms of the deppei group 39 



23. Variation in number of ventrals plus caudals in the forms of the 



deppei group 39 



24. Extremes of variation in color pattern of Pituophis deppei jani (first 



specimen) 45 



25. Extremes of variation in color pattern of Pituophis deppei jani (second 



specimen) 46 



26. The color pattern of Pituophis lineaticollis 50 



27. The color pattern of Pituophis melanoleucus melanoleucus 57 



28. Geographic variation in number of ventrals in Pituophis melanoleucus 



melanoleucus 58 



29. Geographic variation in number of caudals in Pituophis melanoleucus 



melanoleucus 68 



