. Bulletin. Natural history; Natural history. November, 1961 Smith: Amphibians and Reptiles of Illinois 233 Scutellation is apparently identical in the two Illinois subspecies of T. sirtalis. Indi- vidual variation in 91 specimens of both races is as follows: anterior scale rows are 19 in per cent, 20 in per cent; scale rows at mid-body are 18 in per cent, 19 in per cent, 20 in per cent; posterior scale rows are 16 in 2 per cent, 17 in 98 per cent; supralabials are 6-f 6 in 1 per cent, 6-1-7 in 3 per cent, 7 4- 7 in 89 per cent, 7 -]- 8 in 6 per cent, 8 -|- 9 in 1 per cen
. Bulletin. Natural history; Natural history. November, 1961 Smith: Amphibians and Reptiles of Illinois 233 Scutellation is apparently identical in the two Illinois subspecies of T. sirtalis. Indi- vidual variation in 91 specimens of both races is as follows: anterior scale rows are 19 in per cent, 20 in per cent; scale rows at mid-body are 18 in per cent, 19 in per cent, 20 in per cent; posterior scale rows are 16 in 2 per cent, 17 in 98 per cent; supralabials are 6-f 6 in 1 per cent, 6-1-7 in 3 per cent, 7 4- 7 in 89 per cent, 7 -]- 8 in 6 per cent, 8 -|- 9 in 1 per cent; in- fralabials are 8 + 8 in 3 per cent, 9 4- 9 in 7 per cent, 9 -(- 10 in 11 per cent, 10+ 10 in 73 per cent, 11 -|- 11 in 3 per cent, 8 -|- 10 In 3 per cent; preoculars are 1 -I- 1 in 100 per cent; postoculars are 2 + 3 in 2 per cent, 3 4-3 in 95 per cent, 3-1-4 In 1 per cent, 2 -|- 4 in 1 per cent, and 4 -|- 4 in 1 per Fig. 219.— Distribution of Thamnoph'is sirt- alis. Vertical hatching indicates the presumed range of the subspecies sirtalis in Illinois; horizontal hatching, the presumed range of the subspecies semifasciata; crosshatching, the area of intergradation between the two sub- species; solid circles indicate localities repre- sented by specimens examined during this study; open circles, published records believed to be valid. The lower map depicts the total range of the species in the United States. Habits.—The eastern garter snake, al- though occasionally found in shrubbery and in water, is essentially terrestrial. It occurs in a variety of places but seems to prefer a forest-edge habitat. Most individuals of T. sirtalis bite and void excrement when cap- tured. This species feeds on a variety of animals including frogs, toads, salamanders, earthworms, fish, young birds, and leeches. The number of young per brood varies considerably. A captive female gave birth to 27 young in the laboratory in September. Cagle (1942«) recorded a litter of 53 born in e
Size: 1232px × 2029px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., booka, bookcentury1900, bookdecade1910, booksubjectnaturalhistory
