MALACOPTERYGII ABDOMINALES. 477 



Other observers tell us that the herrings, usually buried in 

 the depths of the sea, approach the surface from the necessity 

 of seeking fresh food, and especially to get rid of their eggs 

 and milt. Thus, either in spring or in summer, they ap- 

 proach the mouths of rivers and shores convenient for spawn- 

 ing. Accordingly, the fishery is much more abundant than 

 when the milt is liquid and the eggs ready to escape. It is 

 also possible that the spawning may take place more than 

 once in the year ; its period, at least, is advanced or retarded 

 according to the age of the herrings and the climate in which 

 they live. It is in consequence of this that in certain tracts 

 these fish are to be taken for nearly three seasons, both full 

 and empty. Thus in some parts of the Baltic the spring- 

 herrings spawn when the ice begins to melt, and continue to 

 be seen until the end of the season, the name of which they 

 bear. Then come the larger, or summer-herrings, which are 

 again followed by others, named autumn-herrings. 



These fishes appear to live in the depths of the sea which 

 extends from the forty-fifth degree of latitude as far as the 

 Arctic Pole. 



But, at whatever period the herrings abandon their winter 

 sojourn, they proceed in troops, which are preceded by some 

 isolated males, often some days in advance, and in which 

 there are commonly more males than females. When the 

 spawning commences they rub their belly against the rocks 

 or the sand, agitate themselves, make rapid motions with 

 their fins, place themselves sometimes on one side sometimes 

 on another, imbibing and rejecting the water with force and 

 vivacity. 



We have no very precise notions respecting the time in 

 which the spawn of the herring discloses the young, nor as to 

 the period which is necessary for this species of fish to attain 

 its maximum of size. Its usual length is about ten inches. 



