268 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



the contents of large .sea areas may certainly be gained, provided the 

 apparatus used is sufficiently accurate. 



The importance of such investigations for the physiological knowledge 

 of the sea is greater than may appear at first sight. The first question 

 to be decided was one which had so far hardly been considered seriously, 

 namely, whether the light of the sun exercises in the water of the sea 

 the same germinating influence as in the air and on the land. By these 

 investigations this question has been answered in the affirmative. In 

 December, for example, there ha been found in 10 cubic meters of water 

 more than 100,000,000 of plauts dependent ou sunlight {Rhizosoleriia alata, 

 80,000,000; Chwtoceros, 3 species, 62,000,000), all vigorously increasing, 

 and this entire mass of plants had been produced in the course of about 

 two months. Most of these plants sprouting in salt water belonged to 

 the simplest products of the vegetable kingdom, and therefore appeared 

 particularly adapted to decide general questions of generation. 



Even among the animals living on the coast there are but few which 

 live on firmly rooted plants, and it is an erroneous idea that during au- 

 tumn and winter a sufficient quantity of particles was torn off, which 

 iioated in the sea and served as food for the copepods and other ani- 

 mals, for even in the Baltic the quantity of such floating matter was 

 very smali. The vast majority of marine animals (such as fungi, polyps, 

 worms, ascidians, mussels, a great many snails, crustaceans, and higher 

 animals) live, most of them directly and a few indirectly, on floating 

 matter, which in its lower forms must, therefore, be considered as the 

 animated original material of the life of the sea. 



If we can believe that light, which as a fact exercises a generating 

 intluence in the sea, is used to the fullest extent poss.ble, we arrive at 

 a remarkable conclusion.. As the organic beings in the sea need not 

 protect themselves against lack of salt and moisture, they can be of 

 lighter build and of a lower organization than land aud freshwater 

 animals. That they are of a lower organization can actually be shown. 

 The conclusion would therefore be drawn that the same quantity of 

 light must be able to bind together more carbon and nitrogen in the 

 sea than on the land, aud that in the sea, more organic matter must be 

 generated than on the land, provided not too much light is reflected 

 from the surface of the sea. 



The investigations made in the western part of the Baltic have shown 

 that the quantity of matter floating in its waters is so great as to indi- 

 cate an annual production not much smaller than that of an equal area 

 of land. When it is considered that wherever animals are rooted to 

 the bottom of the sea there must lie floating matter to supply them with 

 food, we feel inclined to the opinion that the quantity of organic and 

 animated beings Heating in (he sea must be enormous. 



It was not astonishing that this powerful generative activity had 

 hitherto almost escaped our observations, as thus far no one has en 



