60 PASSERES. — HIRUNDINID^. 



the front margin. As all three are closed by the 

 usual membrane, the object may be, the decrease of 

 weight by the abstraction of bone, while the surface 

 for the attachment of the muscles of flight remains 

 undiminished. It would be interesting to know 

 whether this structure is found in the Collocalias 

 of the Indian Archipelago, to which the present 

 bird bears a strong outward resemblance. 



The stomach of one, a female, which I dissected, 

 shot while hawking among many others over Blue- 

 iields' grass-piece, in April, was distended almost 

 to bursting with minute insects, which on being 

 dispersed in water, and examined carefully with a 

 lens, proved, I believe exclusively, the winged 

 females of a small species of ant, exceedingly 

 numerous, all more or less comminuted. 



On the 20th of March last, visiting in company 

 with Mr. Hill the estate called Dawkins' Saltpond, 

 the residence of the Spanish Admiral, at the time of 

 the conquest, — I observed several small Swallows 

 flying above some cocoa-nut palms; they uttered, 

 as they flew, a continued twittering warble, shrill 

 but sweet, which attracted my attention. I com- 

 menced a careful search, with my eye, of the under 

 surface of the fronds and spadices of one, and at 

 length discerned some masses of cotton projecting 

 from some of the spathes, which I concluded to be 

 their nests. This conjecture proved correct; for 

 presently I discovered a bird clinging to one of these 

 masses, which I shot, and found to be this White- 

 rumped Swift. On my lad's attempt to climb the 

 tree, eight or ten birds flew in succession from 



