Notes on Virginia in Virginia 



93 



N 

 "35 



"O 



o 

 o 



DO 



200 



250 



SVL Imml 



Fig. 2. Brood size as a function of snout-vent length (SVL, mm) in female Vir- 

 ginia striatula. Solid circles represent Texas specimens (fclark and Fleet 1976); 

 hollow circles represent Virginia specimens. The dash line is the least-squares 

 best-fit line for Texas snakes (brood size - 0.052 SVL - 6.647, r = 0.77); the solid 

 line is the best-fit line for Virginia snakes (brood size = 0.038 SVL - 1.993, r = 

 0.46). 



in which larger females produce larger numbers of ova or young. Statis- 

 tical comparison of their data with ours demonstrates a significant inter- 

 locality difference (F = 20.4); slopes and intercepts of equations predict- 

 ing brood size from female snout-vent lengths are significantly different 

 (see Fig. 2). This means that female V. striatula in Virginia produce 

 more eggs per reproductive attempt than do Texas females of similar 

 size. Absolute brood size, as judged from numbers of fertilized ova or 

 young per female, is significantly higher in Virginia females (t = 2.1; 

 df = 38) than the values given by both Clark and Clark and Fleet, but the 

 difference is not statistically significant in the latter comparison. 



Further reproductive adjustment may occur through increased ova 

 size. Clark (1964) found that the largest right ovarian follicle was larger 

 than 5 mm only twice in a sample that included over 100 females (many 

 of them over 180 mm snout-vent length), and concluded that one of 

 these was abnormal. In our study, largest right ovarian follicles reached 

 12 mm and oviductal eggs were 12-17 mm long. Also, while 100% 

 (24/24) of our females were gravid during the reproductive period, not 

 all mature Texas females were. It may be significant that newborn 



