terrestrial habits in reptiles rather than an 

 all aquatic life. For to most of them 

 water is indispensable to their welfare. 

 Thus the Gila Monster shows this struc- 

 ture as it likes to bathe in shallow water, 

 often for many hours at a time. 



The crescent-shaped openings of the 

 ears are situated not far from the edge of 

 the mouth, between the head and the 

 neck, and are partly concealed and also 

 protected by the overlapping gular fold ; 

 the tympanum is exposed. The animal 

 sees and hears well. The remaining three 

 senses are more or less concentrated in 

 the tongue which is one of the most re- 

 markable features of the Heloderma. It 

 is slightly forked at the tips, half an inch 

 wide and two to three inches long ; it is 

 dark reddish-brown with a shade of pur- 

 ple. When in rest it is drawn together 

 into a small, conical shaped mass, scarce- 

 ly an inch in length. But as soon as some- 

 thing disturbs the usual quietude of the 

 animal the tongue is thrown out immedi- 

 ately. In fact, it is used for smelling, 

 tasting, feeling. It is used for measuring 

 depth and distance, for expressing desire 

 and satisfaction ; and with what rapidity 

 is this instrument of communication pro- 

 jected and retracted! 



A Gila Monster may be trusted to some 

 extent as long as the tongue is freely 

 used, but if that is not the case it is wise 

 to be careful in handling it. Fear and 

 hostility are expressed by deep, long- 

 drawn hisses ; by opening the mouth to its 

 fuhest extent and by quick jerks of the 

 head from one side to the other. 



At the present time these reptiles are 

 not so very common. Ever-prevailing 

 superstition among the ignorant and ex- 

 aggerated bad reputation have brought on 

 a relentless war of extermination against 

 them, so that now in the neighborhood of 

 settlements they are seen seldom if ever. 

 Their center of distribution is more and 

 more confined to the region along the 

 banks of the Gila river in Arizona, al- 

 though less frequently they may still be 

 found as far west as' the Mojave desert in 

 California. But those are wrong who be- 

 lieve that the Heloderma is living only 

 in the most arid portions of the south- 

 west. There are several reasons why the 

 reptile seeks eagerly irrigated places, 

 which are productive of some vegetation, 



for it needs water, food and shady hiding- 

 places. 



In the middle of summer, when even 

 the larger streams are dried up, the Gila 

 Monster retires to some burrow, aban- 

 doned by another animal, or to deep crev- 

 ices in the rocks, and spends there in a 

 torpid state several weeks, until the great 

 rainfalls reheve the country, give fresh 

 plant life and fill again the barren river- 

 beds. This is the animal's summer re- 

 treat. During the course of a year it takes 

 a second and longer one, the regular hi- 

 bernation, that lasts about from Novem- 

 ber to the middle of February, when it 

 resumes its outside life again. It loves 

 to bask in the still mild rays of the sun, 

 but as soon as the heat increases the Gila 

 Monster seeks shelter for the day behind 

 stones and bowlders, under clumps of 

 cacti and in small mesquite groves along 

 the river banks. It roams about only after 

 sunset or early in the morning. The idea 

 that this lizard enjoys the quivering heat 

 on an open Arizona plain, while other sun 

 and heat-loving reptiles keep in hiding,. is 

 as erroneous as many others. Nothing is 

 so absolutely fatal to the Heloderma as 

 to be exposed only for half an hour to the 

 direct rays of the sun in midsummer. An- 

 other reason why it prefers to live in the 

 neighborhood of streams where plant life 

 is more abundant explains itself by the 

 necessity to provide for food. 



Whoever has an opportunity to observe 

 reptiles in confinement for an extended 

 period of time can easily draw conclusions 

 as to their mode of living in freedom. A 

 captive Gila Monster is fed on hens' eggs ; 

 in summer one each week, in winter one 

 every two or three weeks. It refuses ev- 

 ery other kind of food, however tempt- 

 . ingly it may be offered, such as mice, 

 frogs, angleworms, mealworms and the 

 like. It is more than probable that in their 

 wild state they live on a similar diet, con- 

 sisting then of eggs of other lizards, of 

 turtles and of birds. The animal has the 

 reputation of being destructive to the Ari- 

 zona quail. 



Several writers of Natural History add 

 to this a diet of insects, but the embar- 

 rassed locomotion of the Heloderma 

 seems to exclude flying and fast-running 

 prey. Nearly all reptiles which feed on 

 eggs climb, as do some snakes, and as 



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