114 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



are found just as in the spring-herring; but they are frequently over- 

 looked, because the flesh of the great herring is much fatter and looser, 

 and in cutting through its back the knife will easily pass through these 

 soft bones; while in the spring-herring, whose flesh is less fat and there- 

 fore apparently coarser and harder, the knife will not pass through so 

 readily, but will glide along the bone when it meets it. In carefully 

 cutting open the flsh, the two bones above mentioned will easily be found 

 in both kinds. 



Of all the assumed distinguishing marks, then, between the great 

 herring and the spring-herring, only the greater fatness of the former 

 remains. It might be thought that this fatness is caused by the better 

 food which the great herring finds at the greater depth of its abode ; 

 but this cannot be the sole reason. Indeed, there is another and more 

 important cause of this phenomenon. In seeing the great herring lying 

 in the boat after it has been caught, one is immediately struck by its 

 smooth and beautiful appearance ; while the spring-herring, under the 

 same circumstances, is frequently covered with a filthy slime, a mixture 

 of roe and milk, and in pressing the belly of a spring-herring a stream 

 either of roe or milk flows out, which is not at ail the case with the great 

 herring. In opening both, one finds that in the female spring-herring 

 the roe-bags are coarse-grained and soft ; while in the female great her- 

 ring they are fine-grained and hard. It might be supposed that this is 

 a specific difference between them, which, however, is not the case, since 

 it is only caused by the roe-bags being more developed in the spring- 

 herring than in the great herring. In taking the roe-bag of the spring- 

 herring, especially that of a salted one, as its structure can be more easily 

 distinguished, one will find, on opening it with a fine pin, that the roe- 

 bags are not what one would suppose them to be — bags filled with eggs — 

 but that their structure is more complicated. With the aid of the pin, 

 one will easily be able to lay open and follow up certain fine vessels in 

 which the eggs seem to lie, and this is actually the case. The whole roe- 

 bag consists of an infinite number of fine tubes, which, perhaps, can 

 best be compared to greatly-elongated fingered gloves lying exceedingly 

 close to each other and connected by the so-called "binding texure,' 

 which is sometimes hard and stiff and sometimes soft. Where, to con- 

 tinue the figure, the fingers of the glove would join that space which is 

 occupied by the hand, a channel leads the eggs out along the whole 

 length of the roe-bag, and its continuation is another channel which 

 opens in front of the dorsal fin. In the finger-shaped channels, the eggs 

 develop from small cells which gradually grow larger. In the great 

 herring, the egg-cells are very small, and the egg-tubes are connected 

 with each other by a thick layer of binding texture filled with fine blood- 

 vessels. In the spring-herring the egg-cells are more than four times 

 as large ; the egg-tubes are very thin and fine, and there is scarcely any 

 binding texture. In breaking the roe-bag of the great herring in the 

 middle, it seems to consist only of a somewhat brittle-grained mass ; 



