EDIBLE SWALLOWS'-NESTS. 435 



somewhat different in sound from that of the Wood- 

 pigeon. 



About the rocky parts of the coast of Borneo, the 

 Hirundo esculenta skims backwards and forwards all day 

 long, uttering its little cheerful chirp as it eagerly pursues 

 its insect prey. I have taken the nests in nearly every 

 state from the sides of shallow caves, where they adhere 

 in numbers to the walls, like so many watch-pockets. 

 The eggs are white, with a slight pinkish tinge, and are 

 generally two in number. The nests are either white, 

 red, or black, and the natives maintain that these are 

 built by three distinct species, with a white, red, and 

 black breast, but this is erroneous. The Malays assert 

 frequently, moreover, that the nests are formed from the 

 bodies of certain sea-snakes, but there is no doubt that 

 "agal-agal," a marine cellular plant, is the material 

 employed. The Chinese lanterns are made of netted 

 thread, smeared over with gum, produced by boiling down 

 this same plant, which, when dry, forms a firm, pellucid, 

 and elastic substitute for horn or glass. Other species of 

 Swallows, besides the Hirundo esculenta, employ the same 

 glutinous material in the construction of their nest ; but 

 it is always mixed up with grass and matted feathers, so 

 as to render the nests perfectly useless in a commercial 

 point of view. 



Collecting the nests is often a very perilous operation, 

 as may be seen on reading the following extract from 

 Crawfurd's History of the Indian Archipelago. He is 

 describing one of the most productive caves in Java, those 

 of Karang-bolang, on the south coast of the island : 

 " Here the caves are only to be approached by a perpen- 



2 p2 



