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descrix)tive of it. It is this relatively large amount of 

 delicate, easily digested protoplasm of the mantle which 

 renders the oyster so wholesome and nutritious. 



The deposit of this protoj)lasmic material in the mantle, 

 palps and body, stands in intimate relation to the activ- 

 ity of the reproductive organs. During the spawning 

 season oysters are said to be "poor," that is, poor in 

 condition, for at this time the mantle, especially where 

 it lies next the body on each side, is very thin and quite 

 transparent ; the radiating muscles at the edges as well 

 as its vessels and nerves may now be readily studied 

 under the microscope, owing to the transparency and 

 absence of soft granular protoplasm. If we examine at 

 this time the reproductive organs, as a rule, we will find 

 them greatly developed and pouring out their products 

 through two large ducts, the combined caliber of which 

 is not far short of that of the intestine. It will be evi- 

 dent to any thinking mind that if the major part of the 

 food material elaborated by the stomach and intestine 

 goes to the ovary or testes to be transformed into sex 

 products, which are continually thrown off, little of such 

 material can be stored up in the tissues of the body. — 

 This is exactly what happens. In the month of Septem- 

 ber when the oysters for the most part stop spawning, 

 the drain of elaborated material having ceased to flow 

 from the openings of the reproductive organs, it is 

 diverted in another direction, but is retained in the sys- 

 tem, and has to be deposited somewhere in the body. 

 The most extensive deposits of this elaborated living 

 matter occur in the mantle, body and palps, the color of 

 which rapidly changes from the watery transparent con- 

 dition prevalent during the spawning season to a creamy 

 white. The mantle and palps now become very much 

 thicker than before, and their substance appears to be 

 softer, more easily lacerated, and is made up largely of 

 a delicate granular protoplasm, which when broken up 

 has the milky appearance of the reproductive organ 



