. The Canadian field-naturalist. 130 The Canadian Field-Naturalist Vol. 72 There is considerable variation in the number of bars which form complete cross bands in the anterior region of each specimen. This varies from one crossband in specimen No. 41 (deformed, sex not recorded) to 16 complete crossbands in specimen No. 26, a male. VARIATION IN SCALE COUNTS The number of ventral scales in the Ottawa litter varies from 142 to 150 for both males and females (Figure 2). In the series of 42 adults the range for 41 of them is from 144 to 150 for both males and females; the remaining specimen, a fe
. The Canadian field-naturalist. 130 The Canadian Field-Naturalist Vol. 72 There is considerable variation in the number of bars which form complete cross bands in the anterior region of each specimen. This varies from one crossband in specimen No. 41 (deformed, sex not recorded) to 16 complete crossbands in specimen No. 26, a male. VARIATION IN SCALE COUNTS The number of ventral scales in the Ottawa litter varies from 142 to 150 for both males and females (Figure 2). In the series of 42 adults the range for 41 of them is from 144 to 150 for both males and females; the remaining specimen, a female, has 141 ventral scales (Figure 2, sample C). In a litter of 30 individuals from Portland, Leeds County, Ontario, the females have 141-152 ventrals and the males, 143-148 (Figure 2, sample B). There is no sexual dimorphism evident here. Figure 2. Ventral scale counts of male (a) and female (b) Natrix s. sipedon. Each square represents one individual. Sam- ples A and B are litters from, respectively Ottawa, and Port- land, Ontario; sample C consists of adults from Ontario and The number of caudal scales in the Ottawa litter varies from 58 to 71 for females and from 71 to 85 for males (Figure 3,A). Only one male and female have 71 caudals. The range for the 42 adult specimens is not as great and there is no overlap (Figure 3,C). The range for the 30 young Portland is narrow and the sexual dimorphism of the caudal scale count is even more marked (Figure 3,B). n. FUl I â â. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Ottawa Field-Naturalists' Club. Ottawa, Ottawa Field-Naturalists' Club
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