chameleon, a native of Africa, is a creature of far different build and greater 

 range of color change. Sexual differences in color are often marked among 

 lizards. Anohs males, when excited, often distend a throat fold so that bright 

 red skin shows between the scales. A local name of "blood-swallowers" is 

 based on this habit. In most of the swifts the males have patches of bright 

 blue on the sides of the abdomen and sometimes on the throat, which color 

 markings are often absent from the females. Age differences in lizards are also 

 noticeable. The striped lizards, Teiidae, may lose their stripes and develop 

 spots or cross bars as they age. Some species of fivc'lined skink have yellow 

 stripes and bright blue tails in youth. In maturity they take on a more uniform 

 brown. The adult males of some species develop bright red about their heads. 



An odd physical peculiarity of many lizards is familiar and annoying to 

 the collector. It consists of the ability to break off the tail, which continues 

 to writhe and twitch for some time, while the rest of the animal slips quietly 

 away to regenerate its lost parts. The muscles contract so that there is prac' 

 tically no bleeding and apparently no pain. The extreme development of this 

 caudal autotomy is reached in the so-called glass snake, which, when roughly 

 handled, casts off one section after another, until it has lost practically all of 

 its tail, well over half the total length. Needless to say, the popular super- 

 stition that the animal returns and reconnects the cast-off sections has no 

 foundation in fact. Lizards, like snakes, shed their skins, but, unlike snakes, 

 usually in patches or small pieces, rather than as complete skins. 



The alligator is unique among North American reptiles in possessing 

 definite vocal powers. The mating song of the male alligator is a loud bellow- 

 ing that sounds much like the lowing of a bull and may be heard for about 

 a mile. Voice sacs, one on each side of the throat region, are inflated as he 

 calls. The other native reptiles are limited to grunts and hisses, a surprising 

 contrast to the vocal endowments of their lower relatives, the frogs. 



Since lizards are frequently kept as pets, or attempts are made to keep 

 them, a few pointers may be useful. None of them live on sweetened water, 

 as is often stated. They will usually eat insects, such as the beetle larvae called 

 meal worms. All of them, even desert forms, need water, which should be 

 sprinkled around in the cage, where they can lick it up like dew. Most of 

 them will take water greedily in this way, but seem unable to learn to drink 

 from a dish. Warm water for bathing should also be available. They must be 

 kept warm. If once chilled, they often stop eating and soon die. Sand, shade 

 and sunshine should be freely available. Baby alligators, like lizards, must be 

 kept in an even, warm atmosphere. They prefer to take their food under water 

 and will usually eat raw, lean meat, fish or frogs. Experiments indicate that 

 small amounts of cod or halibut liver oil may help to take the place of native 

 sunshine in keeping pet lizards in good condition . 



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