CH^ETURA PELASGICA I CHIMNEY SWIFT. 



57 



cal walls of a chimney or hollow tree. In former times, 

 before the country was settled, the birds roosted and 

 builded in hollows of trees, to which they resorted in 

 thousands sometimes a steady stream of the creatures 

 pouring in at dusk to pass the night. Some such trees 

 have become historic as "swallow-trees," frequented year 

 after year by countless numbers, till the bottom became 

 filled with a mass of debris. Now, like Swallows, they 

 have modified their primitive way, and almost always 

 choose to make their nests in chimneys, whence their 

 name, though too often exposed in such situations to 

 disaster by fire and flood ; 

 as when a soaking rain 

 loosens the mucilaginous 

 fastening of the nest, and 

 the whole comes tumbling 

 down. The " frying-pan " 

 out of which the little 

 birds sometimes fall " into 

 the fire," is one of the 

 most curious of all speci- 

 mens of bird architecture. It consists of a basket-work 

 of bits of twigs, glued together and to the side of the 

 chimney with the sticky saliva of the birds the same 

 substance that in other cases, as those of the species of 

 the East Indian genus Collocalia, forms the famous 

 "edible bird's-nests" used for making soup by the celes- 

 tial heathens. The twigs are gathered in the most skil- 

 ful manner by the birds, who dash past the ends of 

 branches and snap off bits with the beak as quick as 

 thought. The completed basket has a semicircular brim, 

 and shallow cavity, in which are laid four or five pure 

 white, narrowly elliptical eggs, about 0.70 in length by 



FIG. 6. CHIMNEY SWIFT, with 

 mucronate rectrix. 



