626 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



uiue of this phiukloiiic Jiia.ss tliiis lieai)o(l iij) is often ten oi' many times 

 greater tlian that in the inuncdiately adjacent parts of tlie sea. On 

 thecoiitraiy, the i)hiiiktonie mass is extraordinarily poor in pelagic ani- 

 mals and i)lants, Avhoro by tlie emptying of great floods a quantity of 

 fresh water is bronght i nto the sea and its saltness diminished. Johan- 

 nes Milller iM)iiited out how very much the result of pelagic fishery 

 was intlueuoed thereby. Again, on the other handj the rivers day by 

 day bring into the sea a quantity of organic substances which serve as 

 food for the benthonic organisms, and since the benthos again stands in 

 manifold reciprocal relation to the plankton, since the meroplanktonic 

 animals (like the meduste, the j)elagic larvae of worms, echinoderms, 

 etc.) are the means of a considerable interchange between the two, so 

 is it easily understood how the distribution of the holopianktonic ani- 

 mals is also influenced thereby and how irregular becomes the com- 

 position of the plankton. 



ZoocurrenU^ or planMomc streams. — Among the most noteworthy and 

 important phenomena of marine biology is the great .accumulation of 

 swimming bodies which form long and narrow bands of thickened 

 plankton. All naturalists who have worked at the seashore for a long 

 period and have followed the irregular appearance of the pelagic organ- 

 isms know these i)eculiar streams, which the Italian fishermen call by 

 the name " correnti.''^ Carl Yogt, in 1848, pointed out their great impor 

 tance for i:)elagic fishery (17, p. 303). For their scientific designation 

 and their distinction from the other marine currents I propose the term 

 ZoocurrenU -or Zoorema* 



The pelagic animals and plants are so numerous and so closely packed 

 in these zoocurrents as to resemble somewhat the human population in 

 the busiest street of a great commercial city. But millions and millions 

 of small creatures from all the above-mentioned groups of planktonic 

 organisms are crowded confusedly together, and furnish a s])ectacle of 

 whose charm a conception can be formed only by seeing it. If one 

 directly scoo])s up a portion of this motley crowd with a tumbler, not 

 infrequently "the greater part of the contents of the glass (an .actual 

 living animal broth) is composed of tlie volume of .animals, the sm«aller 

 of the volume of water" (3, ]). 171). From a distance tliese "crowded 

 sea-animal streets" are usually discernible from the smoothness which 

 the surface of the sea presents, while close beside it the surface is more 

 or lessri]>pl(Hl. Often one can follow such an "oil-like animal stream," 

 which usually has a breadth of 5 to 10 meters, for more than .a kilometer 

 witliout finding any diminution of the thick crowd of animals in it, while 

 on both sides of it, right and left, the sea is almost vacant, or shows 

 only a few scattered stragglers. At Messina, as at lianzarote, the phe- 

 nomena of the zoocurrents were especially i^ronounced. My companion 



^Rema (used in Messina) is IVoni the Greek prnun = current; conni. 3, n. 172 note. 



