NO. 7 PROTECTIVE ADAPTATIONS McATEE 125 



expected. Forty-five species of l)irds participated in the lizard-eating, 

 including some surprisingly diminutive ones such as the canyon and 

 Carolina wrens and the white-eyed vireo. The road-runner, crows, 

 jays, butcherbirds, and the Carolina wren took lizards most frequently. 

 The chameleon, despite its powers of color change, was identified more 

 often than any other species of lizard, namely, 24 times in the 

 stomachs of 10 species of birds. One swallow-tailed kite had eaten 

 seven specimens at a meal. Horned-toads and swifts, notwithstanding 

 their defenses, which as it happens are diametrically opposed in 

 character, were " among those present " in the stomachs. 



In contrast to the comparatively wide distribution of the lizard 

 determinations, those of snakes were shared by only 26 si)ecies of 

 birds. Crows, hawks, and owls were the most important of these 

 predators ; and it is worth mentioning that the little Carolina wren 

 again unexpectedly appears in the list. The superlatively cryptic 

 green snake (Cyclopliis acsfivits) was eaten by red-shouldered and 

 broad-winged hawks; the swift racers (Bascoiiioii) by five species of 

 hawks and the crow ; the desperately blufiing hog-nosed snakes by the 

 red-tailed and Swainson's hawks ; the stinking garter and water 

 snakes by several kinds of birds ; and the redoubtable and warningly 

 colored king snakes by the red-shouldered hawk. A great blue heron 

 had swallowed a water snake (Natrix fasciofiis) slightly over 25 

 inches long. The only venomous snake identified in the stomachs was 

 Crotaliis conflucntus from a great horned owl but field observers 

 credit another of our birds, the road-runner, with occasional depreda- 

 tions on rattlesnakes. 



Total number of identifications of reptiles, 695 ; percentage of 

 identifications among those of all vertebrates, 5.2173; percentage of 

 species in this class among those of all nearctic vertebrates, 6.1847. 



Other ciicinies. — While some of the larger predatory fresh-water 

 fishes may occasionally devour a young turtle or small snake, actual 

 records of the occurrence have not come to hand. The only one of 

 our amphibians known to be a reptile eater is the bullfrog, which has 

 been observed to eat snakes and newly-hatched turtles and alligators. 

 Reptiles have numerous destructive enemies among their own ranks. 

 Snapping turtles eat snakes ; several kinds of snakes eat turtle eggs 

 and a few the young ; a few species of lizards prey upon other lizards, 

 and a numlier of snakes devour both these animals and their eggs. 

 Snakes are the worst enemies of snakes, such s]^ecies as the racers, 

 king snakes, ring-necked snakes, coral snakes, water moccasin, and 

 copperhead being conspicuous in this respect. The king snakes arc 



