MANUAL OF NATURAL HISTORY. 659 



Several moderate-sized sieves are also requisite for 

 sifting mud and sand, and for washing the contents 

 of the dredge. These may be four or five inches 

 high, and the meshes of their brass or copper bot- 

 toms should be one-tenth of an inch apart. These 

 sieves should be filled, and the contents frequently 

 washed by pouring water on them, or by repeated 

 dipping in the sea, by attaching three strings to the 

 sides, which are held in the hand. When the ship 

 is at anchor " fishing " for Mollusks may be carried 

 on by dropping a fine line with a small hook baited 

 with a bit of flesh. In this manner Olives, Mar- 

 ginellas, Harps, and Volutes may be taken. The 

 same method may be adopted among rocks, and 

 coral-banks, where the dredge cannot be used. The 

 ship's anchor will sometimes bring up shells sticking 

 to the mud on the palms. Where divers are em- 

 ployed valuable species may often be obtained from 

 the stones, sponges, madrepores, &c., they may 

 bring up, and in the middle of which they are con- 

 cealed. The stomachs of fishes of all descriptions 

 should be carefully examined, many among them, 

 especially the ground-feeders, being excellent Con- 

 chologists. Acquaintance should be made with the 

 fishermen of the place, who often procure rare shells 

 in fine condition ; these men are often acquainted 

 with the localities and habits of Hollusca, and must 

 be questioned. 



The markets must be frequented and searched, 

 many interesting species of Mollusks being used in 

 different countries for food, lamps, and other econo- 



