THE " AGAL-AGAL." 137 



have imagined it to consist of sea-worms, of the 

 mollusca order. Forester conceives it to be the 

 sea-qualm, a sort of cuttle-fish found in those seas, 

 or a glutinous sea-plant called agal-agal. Again, 

 it has been supposed they rob other birds of their 

 eggs, and apply the whites of them to their build- 

 ing purposes. 



Haensel's account is curious and unique. He 

 says they build in fissures and cavities of rocks, 

 especially in such as open to the south. In the 

 latter the finest and whitest nests are found. They 

 are small, and shaped like swallows' nests. If 

 perfect, seventy-two of them go to a catty, or 1^ 

 pounds. The best sale for them is in China. As 

 to the substance of which they are made, Haensel 

 says " After the most diligent investigation, I 

 was never able fully to discover this point ; nor do 

 any of the opinions of naturalists with which I 

 have become acquainted appear satisfactory to me, 

 neither have the authors alluded to ever seen the 

 birds. They have remarkably short legs, and are 

 unable to rise if they once fall or settle on the 

 ground. I caught many in this state, and after 

 examining them threw them up into the air, when 

 t hey immediately flew away ; they cannot, there- 

 fore, as some suppose, obtain their materials on 

 the coast and from rocks in the sea. My opinion 

 is, that the nests are made of the gum of a peculiar 



