ARTIFICIAL OYSTER CULTIVATION. 1189 



and in sea-water deprived of all, or more or less of its lime, 

 in order to observe the influence of the composition of the 

 water on the development of the larvae. 



Normally a distinct skeleton should develop. It was 

 found that when the larvae were reared in sea-water 

 deprived of about nine-tenths of its lime, not even a 

 rudimentary skeleton was developed. 



A very trifling diminution in the normal amount of 

 lime, effected by careful precipitation by chemical reagents, 

 was found sufficient to interfere markedly with the growth 

 of the skeleton in the larvae, hence the medium in which 

 some marine germs of life exist would appear to act as a 

 nutritive agent as well as an atmosphere whence oxygen 

 may be obtained for respiration." (f) 



This, again, is^ confirmed by the fact that the cove 

 lobster (usually found near the shore in sheltered places 

 and small harbours, where the bottom is soft and richlv 



j 



covered with dense growths of sea-weeds), has a dull 

 coloured shell containing so little calcareous matter that it 

 yields everywhere to slight pressure, except about the claws. 



(f) As an item of interest in connection with this scientific fact, 

 I cull the following from Public Opinion, October 31, 1890 : 



ARTIFICIAL SEA-WATER. Professor Edward Perrier lately com- 

 municated to the French Academy of Sciences the results of some 

 experiments made by him at the zoological laboratory of the Saint 

 Cloud normal school, upon the use of artificial sea-water for the pre- 

 servation of marine animals, and especially of oysters, in large aqua- 

 riums. The solutions employed have been reduced by him to the 

 following formula for from three to four quarts : Chloride of sodium, 

 8 1 grm. ; sulphite of magnesia, 7 grm. ; chloride of magnesium, 10 

 grm. ; chloride of potassium, 2 grm. During the exposition this 

 solution gave as good results as natural sea-water, with very much less 

 expense. 



