The representatives of the animal kingdom in the desert are fully as strange and curious as are the specimens of vegetable life. It may seem strange that animal life should exist at all in this region of death and desolation, but several forms of creatures seem to find this dread region congenial. In keeping with its surroundings is the _crotalus cerastes_, one of the most deadly of the rattlesnake family. It is known to the frequenters of the desert region as the "sidewinder," because of its alleged propensity for springing sidewise at the object of its wrath, and because it travels with a sidelong motion. The bite of this creature is considered to be certain death, and it is a saying in the West, when some unusually frightful catastrophe overtakes one: "It was a regular sidewinder." The sidewinder is of a grayish color, mottled with dark blotches. It is found in the very heart of the desert, miles and miles from any known supply of water, and it is believed by many to be able to exist without that fluid. Near the borders of the desert the great yellow diamond-back rattler, _crotalus horridus_, is found, as well as a species of constrictor known as the "bull snake." The latter grows to a length of ten or twelve feet and, while formidable to look upon, is perfectly harmless. [Illustration: DESERT LIZARD, CHUCAWALLA, CLOSELY AKIN TO THE GILA MONSTER] Such innocence is not claimed for the Gila monster, _heloderina horridum_, which is found in the southern portion of the Colorado Desert. This huge lizard is like the chameleon in one respect: it changes its color to conform to its surroundings. It is in the main of a yellow hue, with dark markings which change to a gray or to a reddish tint according to the character of the soil about its abiding-place. When it lies quietly upon the earth it is very difficult to detect it because of this resemblance to the soil. The Gila monster attains a length of nearly two feet. It is covered with horny protuberances and scales similar to the horned toad, so called. When angry it makes a hissing noise not unlike that made by a serpent. [Illustration: HORNED TOAD] The horned toad--which is not a toad, but the lizard _phrynosoma_--is an innocent little fellow, attaining a length of six or eight inches at the most. There was a time when his reputation for evil was second only to that of the Gila monster. Now that he is better known he has become a plaything of children and a pet in many a household.