496 JOURNAL, BOMB A Y NA TUBAL HISTORY SOCIETY, Vol. IX. 



of such a situation has not escaped the notice of a species of tern, Sterna 

 ancetheta, Scop, which breeds on one of the islands in hundreds during the 

 monsoon. I have pleasure in presenting the Society with some eggs collected 

 by the lighthouse keepers. These men tell me that the birds lay their eggs 

 on the ground, among the grass, so near each other that the sitting females 

 almost touch, and when the birds rise together they make a cloud that darkens 

 the air. The swifts do not breed on the same island as the terns, but on a 

 smaller one, the peculiar structure of which is evidently the attraction. I was 

 not able to effect a landing on this island, but the accounts I have received 

 of it tally so exactly with a description quoted by P. H. Gosse of a breeding 

 place near Java that I will extract a few sentences. 



" In a little island on the coast of Java, called the Cap, Sir George Staunton 

 found some caverns running horizontally into the side of the rock, in 

 which were numbers of these birds' nests. ' They seemed to be composed of 

 fine filaments, cemented together by a transparent viscous matter, not unlike 

 what is left by the foam of the sea upon stones alternately covered by the 

 tide, or those gelatinous animal substances found floating on every coast. 

 The nests adhere to each other and to the sides of the cavern, mostly in rows 

 without any break or interruption.' a * ° ' Their value is chiefly determined 

 by the uniform fineness and delicacy of their texture ; those that are white 

 and transparent being most esteemed and fetching often in China their 

 weight in silver.' * * * ' When the birds become fledged it is thought time to 

 seize upon their nests, which is done regularly thrice a year, and is effected by 

 means of ladders of bamboos and reeds, by which the people descend into the 

 cavern ; but when it is very deep, rope ladders are preferred. This operation 

 is attended with much danger and several break their necks in the attempt.' " 



I think Sir G. Staunton must be mistaken when he says that the nests are 

 taken after the young birds are fledged. They would be too dirty then to 

 be of much value. They are taken as soon after they are completed as 

 possible. Then the birds build again, and a second and again a third time 

 the nests are taken. This is the chief reason, I believe, of the difference of 

 quality. The nests, as we know now, are not made of any sort of spuma maris, 

 but of a substance secreted by the enormously developed salivary glands of the 

 bird— of spittle in short. In the first set of nests this material is nearly pure, 

 and these are " first sort " nests. When the bird is forced to build again, it 

 ekes out its exhausted supply of saliva with feathers, or other materials, and 

 the nests are " second sort." The third collection- is of still poorer quality. 



It will be observed that Sir G. Staunton says the nest-hunters descend into 

 the caverns. They do the same at the Vingorla Eocks. The caverns appear 

 to be inaccessible from the water below, but there are small openings on 

 the top of the island, through which ladders can be let down. This similarity 

 in the situations selected by the birds is very curious. I have not heard 

 of any necks being broken at the Vingorla Rocks, but the operation of get- 

 ting the nests is admitted to be very dangerous. 



