164 



BRANCH VERTEBRATA. 



FIG. 27T 



Coo' cy gus a mer i cd' nus. 

 Yellow-billed Cuckoo. (\.) 



The Cuckoos inhabit all countries. Their toes are in 

 pairs, the exterior being somewhat versatile, in one species 



quite so. The only species found 

 in England is parasitical in its 

 incubation, like the American 

 cow-bird. Its young hatches 

 simultaneously with its nest 

 companions, whom it soon tosses 

 out upon the ground. 



The Yellow-billed Cuckoo, 

 with its near relative, the Slack- 

 billed [C. erythrophthalmus] , 

 (e ri trof thal'mus), is found 

 throughout North America. 

 They are both fond of hairy caterpillars, which few birds 

 will eat.* Unlike the European species, they build a 

 nest, though it is rude and airy. Laying their eggs, how- 

 ever, at long intervals, 

 they protract the breed- 

 ing season from one to 

 four months ; the same 

 nest often containing a 

 new egg, one just hatch- 

 ing, a young bird partly 

 fledged, and another 

 ready to fly. 



The Road Runner, a ground birdf found in south- 

 western North America, is so swift of foot that for a 

 quarter of a mile it will outrun a fleet horse. 



* The Cuckoo's gizzard is often found lined with caterpillars' hairs, so tena- 

 ciously adhering by their minute barbs as to require microscopic examination to 

 prove that they do not grow from the coating of the stomach. 



t It often carries the beetles and snails on which it feeds to a particular spot in 

 order to break the shell, and thus piles of the broken fragments collect at that place. 



FIG. 278 



Geococ'cyx California' nus. RoadRunner, 



