THE HORNED TOADS. 



The Horned Toads form an interest- 

 ing- group of Lizards which are related 

 to the iguanas of the tropical forests of 

 America. They are, however, terrestrial 

 lizards, inhabiting the plains of South- 

 western United States and Mexico. 

 Their short, broad and more or less 

 flattened bodies, rounded heads and short 

 tails give these animals quite a striking 

 resemblance to the common toad. Hence 

 their common name. In one respect, 

 however, they are not at all like the toad. 

 The head is armed behind with a row of 

 quite formidable horny spines, and in 

 some of the species shorter ones are also 

 present on the top of the head and on 

 various parts of the body. As these liz- 

 ards are slow in motion, the horns con- 

 stitute one of their chief means of de- 

 fense. When in the presence of an en- 

 emy ''the muzzle is depressed and the 

 horns are elevated. The back is also 

 arched." The utility of the horns as a 

 means of defense has been ampl}^ proven. 

 The dead bodies of snakes have been 

 found with the horns protruding through 

 the skin of the body near the head. But 

 this is not their only means of defense. 

 From birds they are protected by their 

 coloration, which is a somber mixture of 

 brown, black and yellowish, and when 

 quietly resting on sands or rocks in the 

 open they quite closely resemble stones 

 covered with lichens of varying shades 

 of color. Abundant as they are in some 

 arid regions of the Southwest, they fre- 

 quently escape the notice of the observer 

 because of their coloration. In such re- 

 gions, too, they can take refuge beneath 

 the protecting spines of the Agaves and 

 the branches of the prickly Opuntias. 

 Dr. Leonhard Stejneger considers the 

 Horned Toads a most striking illustra- 

 tion of protective mimicry. Of one spe- 

 cies he says : 'Tn the cedar and pine 

 belts of the San Francisco Mountains the 

 dark color of the soil and stones cover- 

 ing the surface is closely matched by the 



ground color of the Horned Toad, while 

 the greenish gray and orange-colored 

 markings which somewhat irregularly 

 adorn their backs are perfect imitations 

 of the lichens covering the rocks and peb- 

 bles among which these odd looking crea- 

 tures live. Near the rim of the Grand 

 Canyon of the Colorado, on the other 

 hand, the ground is covered with small 

 pebbles of variously colored sandstone, 

 ranging from a clayey white to brick red 

 and dark brown, and the specimen which 

 I collected there is such a faithful repro- 

 duction of the surroundings that it would 

 undoubtedly have remained undetected 

 had it not been moving. Even more re- 

 markable are the specimens which Dr. 

 Merriam collected in the black lava belt. 

 One of these was brought to camp alive." 

 Dr. Stejneger made a careful study of 

 this specimen and found that it had verv 

 closely imitated the color of the lava, in- 

 cluding even its glossy appearance. 



One of the most remarkable habits of 

 at least one of the species, and possibly 

 of all the Horned Toads, is the power of 

 ejecting jets of blood from the eyes. This 

 power is rarely exercised and seeminglv 

 only when greath^ irritated. Professor 

 L-. M. Underwood relates the following 

 instance, which also illustrates some of 

 the other habits of the Horned Toads 

 when angered: "In 1885 a student of 

 mine recived a specimen of Horned Toad 

 from California. In examining the ani- 

 mal I took occasion to turn him on his 

 back, using a lead pencil for the purpose. 

 The animal resented this treatment and 

 showed considerable anger, opening his 

 mouth and puffing up his body. Irritat- 

 ing the animal still more, he grew more 

 and more enraged, until finally blood 

 spurted from just above his eye, which 

 was fired at least a foot from the animal, 

 as several spots struck my arm consid- 

 erably above my wrist. After spurting 

 the blood the toad became limp and col- 



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