ILLUSTRATIONS 



Platk I 



Map, showing the location of the pearl beds of Mindanao and Sulu. (Drawn 

 in the Bureau of Science from Coast and Geodetic Survey charts 4200 

 and 4722.) 



Plate II 



The gold-lip pearl oyster, Margaritifera maxima Jameson. 



Plate III 



a, a young specimen of the turban shell, Turbo marmoratus Linnseus; b 

 and c, two views of an adult turban shell ; d, a top shell, Trochiis niloticus 

 Linnaeus, cut through the vertical plane; e and /, two views of a top 

 shell ; g, a top shell, showing cuts made for buttons in the partition walls. 



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