to noonday heat and sunshine, but do make frequent excursions from one shady 

 spot to another. The casual observer may easily mistake a temporary stop in 

 bright sunlight for the commonly described but apparently rare ''basking in 

 hot sun'\ Many of them enjoy exposure to mild sunshine, and most of them 

 have fairly high optimum temperatures. The Crocodilians share this preference 

 for high temperatures. A growth of about a foot a year has been recorded for 

 captive alligators kept at the optimum temperature of about 80° Fahrenheit. 



Although lizards are generally feared by people unacquainted with their 

 habits, only one species, the Gila monster, is poisonous. This animal, which 

 gets to be about two feet long, is found in southwestern United States and 

 Mexico. It is usually vicious and untrustworthy, when first captured. Since 

 its poison glands are in its lower jaw, so that the poison cannot be efficiently 

 ejected unless the animal turns upon its back, and since its poison 'Conducting 

 teeth are grooved, instead of hollow needles as in most of our poisonous snakes, 

 its bite is not always attended with serious consequences to humans. Its poison 

 is said to be as powerful as that of the rattlesnake, however, and no chances 

 should be taken. Unlike the poisonous snakes, the Gila monster retains its 

 hold with great tenacity, so that it is almost impossible to shake it off. 



Most lizards feed on insects. A few devour other lizards. The Gila 

 monster, in captivity, takes readily to hens' eggs and at liberty would probably 

 devour any available birds' eggs. The chuckawalla is herbivorous and is used 

 by the Indians for food. Many lizards have thick, fleshy tongues and capture 

 their prey by sudden rushes. The horned "toads" resemble toads in eating 

 habits as well as in appearance, for they have extensible tongues, which can 

 be projected to adhere to insects and retrieve them. The striped lizards have 

 narrow, forked tongues much like those of snakes. 



Most of the lizards are oviparous. Many bury their eggs, often in warm, 

 damp sand, and pay them no further attention. Some species deposit eggs 

 in rotting logs, damp moss and similar places and remain with them to help in- 

 cubate or protect them. The glass snake is one of the lizards that broods its 

 eggs. It is possible that the brooding habit is more general among lizards than 

 has previously been supposed. A few lizards, such as the horned toads, pro- 

 duce living young, retaining their eggs within the body until time for hatching. 

 The alligator lays eggs about the size and shape of goose eggs in a piled-up 

 mass of decaying vegetation in a swamp or similar habitat. It is reported to 

 watch over its eggs and to open up the nest when they hatch. It seems probable 

 that it guards its young for some time thereafter. 



Color variations often puzzle the collector and taxonomist and may be 

 correlated with emotional state, sex and age. The American chameleon, Anolis, 

 popularized by circus hawkers, turns from a dull brown to a vivid green when 

 excited and often when sleeping. Environment affects its color only indirectly, 

 for there is little attempt to match body color with surroundings. The true 



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