Forest Preserve District of Cook County, Illinois
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Some Lizards of the Middle West
Nature Bulletin No. 344-A   May 10, 1969
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation

More than 2,500 kinds of lizards are now known in the world, and they vary more widely in size, shape, color and habit than any of the other three groups of reptiles -- the snakes, the turtles and the alligators. Three kinds of lizards are known to live within 50 miles of Chicago but they are so scarce, and so wary or secretive, that the total number found by all the reptile enthusiasts is often only one or two a year. Farther south they become more common and farm boys know them well.

Lizards, having dry scaly skins that they shed from time to time, should not be confused with the salamanders which, altho also four- legged and cold-blooded, are amphibians -- not reptiles -- and have moist smooth skins. The only live lizards that most of us ever see are in the zoos, notably the sluggish Gila Monster which is one of the only two poisonous species; or a friendly little Horned "Toad" which someone may have brought back from the Southwest; or one of those little American chameleons sometimes sold at carnivals or county fairs in states where that is still permitted.

The strangest of our local lizards is the shiny Glass Snake. It may be two or more feet long and is legless but, unlike snakes, it has ear openings and can close its eyes. Like many lizards it is mostly tail. When caught or injured, this creature can shed that long tail and later grow a new one -- a peculiarity which has given it the name "Joint Snake", because many folks still believe that it can back up and join onto the original tail. Burrowing in dry meadows, they feed on insects, spiders and land snails. In July the female lays about a dozen inch- long oval eggs in loose soil or leaves and coils around them during the two months of incubation.

Some lizards dart and run very swiftly but perhaps the fastest of them all is the Sixlined Race Runner, about pencil length, found in southeastern United States and occasionally near Chicago. In a wild dash for safety, it gets up on its hind legs and, balanced by a long slender tail, streaks over the ground at speeds supposedly up to 18 miles per hour. They have three narrow yellow stripes down each side of the back, and in breeding season the male' s belly has patches of brilliant blue with which he challenges his rivals to battle. In his elaborate courtship he scoots over the ground in figure eights, biting and poking the necks of others in the colony. Early in summer, each female lays a few eggs in a dry sandy area and leaves them to be hatched by the heat of the sun.

Of three or four little lizards with smooth shiny scales, called skinks, known to live in or near Illinois, the 7-inch Blue-tailed Skink is the only one found in woodlands around Chicago. Its tail breaks off easily and wriggles for some time thereafter but it soon grows a new one. The female lays six or more eggs under rubbish, or loose bark on fallen logs, and jealously guards them. The young are glossy black with five yellow lines down the back and a brilliant blue tail. As they grow, these colors fade and the male, especially, becomes a uniform brown with a reddish head. They live mostly on insects, spiders and snails.

The Fence Lizard, or Swift, is rather common in woodlands of southern Illinois where it divides its time between trees and the ground. About 6 inches long, it has a chunky body and a long slender tail which is very brittle. They love to bask in the sun and their rough bristly skin, marked on the back with a dark V-shaped bars, blends well with rocks and fallen logs. Also common, in hotel lobbies, are Lounge Lizards.

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