110 



BULLETIN 61, UNITED STATES NATIONAL MUSEUM. 



this trait indicated hj the material examined. The tail length is 

 strikingly constant for this gronp, which may be in part but not 

 entirely explained by the small amount of material; the length ex- 

 ceeds that of any other form in the genus, the extremes being .32 -.38, 

 the average between .33-.36 (see fig. 43). As is to be expected from 



174 



V 



C) 



— ^ > V 



ii 



i'c 



Fig. 42. 



166 



158 



150 



Bay St. Louis, Pensacola, Gainesville, Kissimmee, Lcinou Cil.v, 

 Mississippi. Florida. Marion Co., Georgiana, Florida. 



Florida. Enterprise, 

 Orlando, 

 Little Sara- 

 sota B:iy, 

 Florida. 



~DlAGR.\M SHOWING THE VARIATION IN THE NUMBER OF VENTRAL SCUTES IN ThAMNOPHIS 



SAURITUS SACKENI. 



the length of the tail, the number of subcaudal scutes also exceeds 

 that of any other form. As show^n by the diagram (fig. 44), the 

 extremes are 109-134 and the averages for the different localities 



Bay St. Louis, Pensacola, Gainesville, Kissimmee. Lemon City, 

 Mississippi. Florida. Marion Co., Georgiana, Florida. 



Florida. Enterprise, 



Orlando, 

 Little Sara- 

 sota Bay, 

 Florida. 

 Fig. 4,'(.— Diagram showing the variation in the proportionate tail length in Thamnophis 



sauritus sackeni. 



between 120 and 127. Here again no geographic variations can be 

 detected. 



As is generally the case in the forms of the Sauritus group, there is 

 little variation in coloration in sdclrni. The usual A'ariation of light 

 to dark in the ground color is present, the lighter individuals being a 



