ORDER ACCIPITRES. 135 



serve to retain the nest, which ascends or descends along these 

 stalks, according as the surface of the water on which it reposes 

 rises or falls. 



The last nest which we shall notice in this place is that very 

 celebrated one of the hirundo esculenta, and which constitutes 

 a dainty in great request among the Chinese and Japanese. 

 This, swallow constructs its nest in the hollows on the steep 

 shores, or in the caverns of the MoUuccas, and many other 

 islands in the Indian ocean. In Java these nests form a con- 

 siderable article of commerce, and are sold extremely dear, 

 when they are quite fresh, and not dirtied during the process of 

 incubation. These nests are made with the branches of a sort 

 of fucus, discoloured and agglutinated by the swallow. It was 

 for a long time imagined that these nests were formed with the 

 spawn of fishes, or other animal substances, collected by this 

 bird on the surface of the sea. It has, however, been clearly 

 ascertained by M. Valenciennes, that they are made of the 

 branches of a certain fucus, by an accurate comparison of some 

 colourless fucus brought from the Molluccas, with the compo- 

 sition of the nests in question, deposited in the King's Cabinet. 

 This comparison was made by M. Desfontaines, that most 

 expert botanist. This is the less surprising, when we consider 

 that many vegetable productions of the Indian ocean are 

 edible, and that one of them, the fucus sacchariferus, contains 

 a large portion of sugar. 



Is is also proper to state, that M. Reinwardt, a celebrated 

 professor, who made a long stay at Java, was of opinion that 

 this bird consolidates its nest with a viscous and glutinous 

 humour, secreted in its very large parotid glands. The sums 

 netted by the sale of these nests are very considerable. Near 

 the Goenong-Goetoe, one of the largest volcanos in Java, 

 there is a cavern from which the proprietor derives a revenue 

 of more than fifty thousand Dutch florins per annum. 



As a winged animal, like the bird, could not bear about 

 with it its offspring in the womb, like the mammifera, nature 



