The Spring and Summer of 1894. 



439 



masses. At the same depth the above-named alga 

 seemed especially to flourish, while parts of it rose up to 

 the surface. It was evident that these accumulations of 

 diatoms and alga remained floating exactly at the depth 



From a\ 



BLESSING FISHING FOR 



\_Photograph. 



where the upper stratum of fresh water rests on the sea 

 water. The water on the surface was entirely fresh, and 

 the masses of diatoms sank in it, but floated on reaching 

 the salt water below. 



