2S6 Pearls. 



and placed in two parallel rows upon the mantle 

 or fleshy surface of the animal. A sufficient number 

 having been placed on one side, the operation is 

 repeated on the other. Stimulated by the irritating 

 bodies, the suffering animal spasmodically presses 

 against both sides of its testaceous skeleton, keeping 

 the matrices in place. This being done, the mussels 

 are deposited one by one in canals, or stream's or 

 pools connected therewith, five or six inches apart, 

 at depths of from two to five feet, in lots of from 

 five to fifty thousand. 



If taken up in a few days after the introduction 

 of the mould, they will be found attached to the 

 shell by a membraneous secretion, which at a later 

 period appears as if impregnated with calcareous 

 matter, and finally layers of nacre are deposited 

 around each neucleus, the process being analogous 

 to the formation of calculary concretions in animals 

 of a higher development. A ridge of marl generally 

 extends from one pearly tumour to another, con- 

 necting them all together. 



About six times in the course of the season, 

 several tubs of night-soil are thrown into the 

 reservoir for the nourishment of the animals, Great 

 care is taken to prevent goat manure from falling 

 in, as it is highly detrimental to the mussels, 



