communication 

 Johansen & Lenfant 1972 



Thorson 1968 

 Johansen & Lenfant 1972 

 Korshuev et al, 1957 

 Pough, unpublished 

 Pough, unpublished 

 Pough, unpublished 



Mean ± s .e. 



27. Oil. 2 



8.0 



8.2+1.80 



Colubridae (26 species) 

 Cerberus rhynakops 



32 



3.6 



Pituophis melanoleucus 



Feder, personal 

 communication 

 Button 1958 

 Khalil & Abdel-Messeih 1963 

 Pough, unpublished 

 Pough, unpublished 

 Pough, unpublished 

 Coin & Jackson 1965 

 Wintrobe 1933 

 Hutton 1958 

 Pough. unpublished 

 Pough 1976 

 Coin & Jackson 1965 

 Pough, unpublished 

 Binyon & Twigg 1965 

 Motelica et al. 1967 

 Munday & Blane 1961 

 Nair 1955 

 Khalil & Abdel-Messeih 1963 

 Coin & Jackson 1965 

 Hutton 1958 

 Pough, unpublished 

 Wintrobe 1933 

 Coin & Jackson 1965 

 Dessauer 1970 

 Pough 1976 

 Pough 1978 

 Ryerson 1949 



