258 THE REASON WHY: 



" Rap, rap, rap, rap, I hear thy knocking bill, 



Then thy strange outcry, when the woods are still." MONTGOMERY. 



The word zygodactyli is compounded of zygoo, "to jom," and 

 daktylos, a finger. 



797. Why are .the supposed ravages of woodpeckers beneficial 

 rather than otherwise? 



.Because they bore only those trees which insects have previously 

 attacked, and thus diminish very considerably the numbers of such 

 as are injurious to our forests. 



798. Why are the extremities of the feathers in the tail of the 

 woodpecker hard and elastic like whalebone, and with the shaft 

 particularly prominent? 



Because this quality in the bird's 

 tail affords a prop, or fulcrum, as it 

 rests against a tree ; and no other 

 contrivance could enable the bird to 

 maintain its position when throwing 

 back its head to give due force to 

 the bill in hammering at the bark 

 of the tree. 



799. Why is tJie bill of the parrot so thick and powerful ? 



This member, so unlike that of other frugivorous birds, is 

 admirably calculated for the principal offices it has to perform, 

 viz., breaking the shells and stones of the hardest fruits and seeds, 

 and as a strong organ of prehension and support when climbing or 

 moving from one position to another. 



800. In their native woods, the movements of the parrot tribe are marked by an 

 ease and gracefulness we never see exhibited in a state of confinement. They 

 climb about the branches in every direction, and suspend themselves from them in 

 every possible attitude, in all which movements they are greatly assisted by their 

 hooked bills, which are used, like the foot, as an organ of prehension and support.* 



* naturalists' Library. 



