XI.-BIOLOGICAL ACTION OF THE SALTS CONTAINED IN SEA- 

 WATER FROM THE POINT OF VIEW OF THE MAINTENANCE 

 OF MARINE ANIMALS.* 



By H. a. Coutan'ce. 



IFro/essor at theschooh of naval medicine, pharmacist in chief to thr Nari/, and President 

 of the Academical Society of Brext.'] 



Marine animals are organisms of excessive sensibility, and are sub- 

 ject to the varied influences of the element in which they live. The 

 disposition of the fauna of the sea is dependent on the composition of 

 the salt water, the nature and quantity of the gases dissolved, and the 

 temperature, force, and operation of the currents. The succession of 

 species of marine animals in geological strata, little different from each 

 other in the nature of the deposits, shows plainly that influences which 

 appear to us but of slight importance, have governed this succession 

 itself. 



I wished to ascertain the influences which the modifications in the 

 nature of the salts dissolved might have on the marine animals, and 

 with this view I entered upon a series of researches for the i)urpose of 

 establishing a biological parallel between these salts. My experiments 

 have been solely devoted to the molkiscs of our sliores, especially those 

 which form articles of food for our f»opalation. 



The sea water contains for every 1,000 grams an average of 35 grams 

 of different salts in solution, among which chloride of sodium appears 

 to exercise the most important influence on animal life. The sup])osi 

 tion is doubtless permissible that the other substances are useful to a 

 certain limited extent, and have, apparently at least, no Inutful in 

 fluence. 



* ^^ Action hiologique des seh de Veau de mer au point de rue de Ventretien dis animaux 

 marins." From Bullefm mensuel de la Soci4te nationale d^AccUmatation de France, 3d 

 series, vol. X, No. 2, Febrnary, 188;5. Read at the 19th meeting of the learned 8ocie- 

 ties, in 1882, in general session. Translated from the French by Herman Jacobsok. 

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