2 o 6 Birds Every Child Should Know 
breasts. You may know the yellow-billed 
cuckoo by the yellow lower-half of his long, 
curved bill, his cinnamon-brown wings and the 
conspicuous white thumb-nail spots on his 
dark tail feathers. If you were to dip your 
thumb in white paint, then pinch these outer 
quills, you would leave similar marks. 
Most birds will not touch the hairy, fuzzy 
caterpillars — very disagreeable mouthfuls, one 
would think. But happily cuckoos enjoy them 
as well as the smooth, slippery kind. I guess 
they like the custard inside, said a little boy 
I know who had stepped on a fat caterpillar on 
the path. “ Cuckoos might well be called 
caterpillar birds,” wrote Florence Merriam 
Bailey, “for they are so given to a diet of the 
hairy caterpillars that the walls of their stom- 
achs are actually permeated with the hairs, and 
a section of stomach looks like the smoothly 
brushed top of a gentleman's beaver hat.” 
When you see the webs that the tent cater- 
pillar stretches across the ends of the branches 
of fruit and nut trees toward the end of summer, 
or early autumn, watch for the cuckoo’s visits. 
Orioles, also, tear open the webs to get at the 
wiggling morsels inside, but they leave dead 
and mutilated remains behind them, showing 
that their appetite for web worms is less keen 
than that of the cuckoos, who eat them up clean. 
Fortunately the caterpillar of the terribly 
