178 Birds of Buzzard's Roost 



beautiful structure certainly shows considerable intelligence 

 on the part of the builder. Two white eggs are laid to a set, 

 one every other day, and these are frequently deposited before 

 the nest is more than half completed, the female finishing it 

 gradually after incubation has commenced, and sometimes 

 adding additional lichens on the outside, even after the young 

 have been hatched." 



As soon as incubation commences the male appears to lose 

 all interest in his spouse for the time being and leads an easy, 

 careless life, and lets her attend to the incubation and feeding 

 of the young. Incubation lasts about fourteen days. When 

 hatched the young are blind and they do not open their eyes 

 until they are about a week old. They are large enough to 

 leave the nest in from sixteen to twenty-one days. The mother 

 feeds them by regurgitation and their food consists of the nec- 

 tar of various flowers and very tiny insects. 



The food habits of the ruby-throat are interesting. Its 

 food consists of minute insects and nectar, which it extracts 

 from the deep chalices of flowers and sap which it obtains, 

 from trees where the sapsucker has perforated them. Pro- 

 fessor Judd of the United States Department of Agriculture 

 says, that the adult birds feed on insects to a much greater ex- 

 tent than they do on nectar, and that they destroy many gnats, 

 ants, and minute parasitic wasps ; and that the young nestlings 

 are fed on flies, beetles and spiders by the process of regurgi- 

 tation, a habit that appears to be much more general among 

 birds than formerly supposed. To enable the hummingbird to 

 obtain its food, it is provided with an unusually long beak and 

 a wonderfully constructed tongue. The tongue is long, thread- 

 like, and divided into two tubes which run throughout its en- 

 tire length, and is capable of being protruded to a consider- 

 able distance from the point of the tip of the beak, and can be 

 bent in any direction. At the throat it joins a curiously forked 

 bone which passes on' either side of the neck, and around the 

 back of the head, ending in the forehead, like that of the flicker 

 and is illustrated in the chapter entitled "The Flicker," which 

 see in this connection. It is this and the muscles that control 

 it which enables the bird to protrude its tongue. With its 

 tongue which acts like a suction pump, it has the power of 



