THE PERCHING BIRDS 



interested me most of all was the manner in which the birds assisted each other in 

 their search for food, because it appeared to explain the use, in the economy of na- 

 ture, of the differently-formed bills in the two sexes. To divert the birds, I intro- 

 duced a log of decayed wood infested with the hu-hu grub. They at once attacked 

 it, carefully probing the softer parts with their bills, and then vigorously assailing 

 them, scooping out the decayed wood till the larva or pupa was visible, when it was 



MALE AND FEMALE HUIAS. 

 (One-third natural size.) 



carefully drawn from its cell, treated in the way above described, and then swal- 

 lowed. The very different development of the mandibles in the two sexes enabled 

 them to perform separate offices. The male always attacked the more decayed por- 

 tions of the wood, chiseling out his prey after the manner of some woodpeckers, 

 while the female probed with her long pliant bill the other cells, where the hardness 

 of the surrounding parts resisted the chisel of her mate. Sometimes I observed the 



