April 2S, 1881] 



NA TURE 



607 



ordinary steam-engine. The mirror is of silvered copper ; 

 the boiler is blackened and is surrounded by a glass 

 cylinder, which of course permits the passage of the sun's 

 heat through it, but obstructs its escape after absorption. 

 The whole thing costs 4000 francs, and it could be used 

 in many countries for at least 200 days in the year. 



G. F. RODWELL 



THE HERRING ^ 



IT is now nineteen years since my attention was first 

 specially directed to the natural history of the her- 

 ring, and to the many important economical and legal 

 questions connected with the herring fisheries. As a 

 member of two successive Royal Commissions, it fell to 

 my lot to take part in inquiries held at every important 

 fishing station in the United Kingdom between the years 

 1862 and 1865, and to hear all that practical fishermen 

 had to tell about the matter ; while I had free access to 

 the official records of the Fishery Boards. Nor did I neg- 

 lect such opportunities as presente.l themselves of study- 

 ing the fish itself, and of determining the scientific value 

 of the terms by which, in the language of fishermen, the 

 various conditions of the herring are distinguished. 



Diligent sifting of the body of evidence thus collected 

 and passed under review, led to the satisfactory clearing 

 away in my own mind of some of the obscurities which, at 

 that time, surrounded the natural history of the fish. But 

 many problems remained, the solution of \vhich was not 

 practicable by investigations which, after all, were only 

 incidents in the course of a large inquiry, embracing a 

 vast number of topics beside herrings and herring 

 fisheries ; and it is only within the last few years that the 

 labours of the German West Baltic Fishery Commission 

 have made such large additions to the state of our 

 knowledge in 1865, that the history of the herring is 

 brought within measurable distance of completeness. 



Considering the vast importance of the herring fisheries 

 of the Eastern Counties, it occurred to me when the 

 President of the National Fishery Exhibition did me the 

 honour to ask me to address you, that nothing could be 

 more likely to interest my audience than a summary 

 statement of what is now really known about a fish 

 which, from a fisherman's point of ^■iew, is probably 

 the chief of fishes. 



I am aware that 1 m.-iy lay myself open to the applica- 

 tion of the proverb about carrying coals to Newcastle, 

 if I commence my observations with a description of the 

 most important distinctive characters of a fish which is 

 so familiar to the majority of my hearers. And perhaps 

 it is as well that I should at once e.\press my belief that 

 most of you are as little likely to mistake a herring for 

 anything else as I am. Nay, I will go further. 1 have 

 reason to believe that any herring-merchant, in a large 

 way of business, who may be here, knows these fish so 

 much better than I do, that he is able to discriminate a 

 Yarmouth herring from a S:otch herring and both from 

 a Norivay herring ; a feat which I could not undertake to 

 perform. But then it is possible that I may know some 

 things that he does not. He is very unlike other fishermen 

 aad fish-merchants with whom 1 have met, if he has any 

 but the vaguest notions of the way of life of the fish ; or 

 if he has heard anything about those singularities of its 

 organisation which perple-; biologists ; or if he can say ex- 

 actly how and why he knows that a herring is not a sprat, 

 a shad, or a pilchard. And all kinds of real knowledge 

 and insight into the facts of nature do so bear upon one 

 another and turn out in strange ways practically helpful, 

 that I propose to pour out my scientific budget, in the 

 hope that something more may come of it than the grati- 

 fication of intelligent curiosity. 



If any one wants to exemplify the meaning of the word 



■ A leclure delivered by Prof. Huxley at the National Fishery Exhibition, 

 Xorwiclt, April 21, 1S81. 



"fish" he cannot choose a better animal than a her- 

 ring. The body, tapering to each end, is covered with 

 thin, flexible scales, which are very easily rubbed off. 

 The taper head, with its underhung jaw, is smooth and 

 scaleless on the top ; the large eye is partly covered by 

 two folds of transparent skin, like eyelids — only immov- . 

 able and with the slit between them vertical instead of ' 

 horizontal ; the cleft behind the gill cover is very wide, 

 and, when the cover is raised, the large red gills which 

 lie beneath it are freely exposed. The rounded back 

 bears the single moderately long dorsal fin about its 

 middle. The tail fin is deeply cleft, and on careful in- 

 spection saiall scales are seen to be continued from the 

 body, on to both its upper and its lower lobes, but there is 

 no longitudinal scaly fold on either of these. The belly 

 comes to an edge, covered by a series of sharply-keeled 

 bony shields between the throat and the vent ; and 

 behind the last is the anal fin, which is of the same 

 length as the dorsal fin. There is a pair of fore-limbs, or 

 pectoral fins, just behind the head ; and a pair of hind- 

 limbs, or ventral fins, are situated beneath the dorsal fin, 

 a little behind a vertical line drawn from its front edge, 

 and a long way in front of the vent. These fins have 

 bony supports or rays, all of which are soft and jointed. 



Like most fishes, the herring is propelled chiefly by the 

 sculling action of the tail-fin, the rest serving chiefly to 

 preserve the balance of the body, and to keep it from turn- 

 ing over, as it would do if left to itself, the back being 

 the heaviest part of the fish. 



The mouth of the herring is not very large, the gape 

 extending back only to beneath the middle of the eye, and 

 the teeth on the upper and lower jaws are so small as to 

 be hardly visible. Moreover, when a live herring opens 

 its mouth, or when the lower jaw of a dead herring is 

 depressed artificially, the upper jaw, instead of remaining 

 fixed and stationary, travels downwards and forwards in 

 such a manner as to guard the sides of the gape. This 

 movement is the result of a curious mechanical arrange- 

 ment by which the lower jaw pulls upon the upper, and I 

 suspect that it is useful in guarding the sides of the 

 gape when the fish gulps the small living prey upon which 

 it feeds. 



The only conspicuous teeth, and they are very small, 

 are disposed in an elongated patch upon the tongue, 

 and in another such patch, opposite to these, on the fore 

 part of the roof of the mouth. The latter are attached to 

 a bone called the vomer, and are hence termed vomerine 

 teeth. But, if the mouth of a herring is opened widely, 

 there will be seen, on each side, a great number of fine, 

 long, bristle-like processes, the pointed ends of which 

 project forwards. These are what are termed the gill 

 ra'cers, inasmuch as they are fixed, like the teeth of a rake, 

 to the inner sides of those arches of bone on the outer 

 sides of which the gills are fixed. The sides of the 

 thro.1t of a herring, in fact, are as it were cut by four deep 

 and wide clefts which are separated by these gill arches, 

 and the water which the fish constantly gulps in by the 

 mouth flows through these clefts, over the gills and out 

 beneath the gill covers, aerating the blood, and thus 

 eflecting respiration, as it goes. But since it would be 

 highly inconvenient, and indeed injurious, were the food 

 to°slip out in the same way, these gill rakers play the 

 part of a fine sieve, which lets the water strain off, 

 while it keeps the food in. The gill rakers of the front 

 arches are much longer than those of the hinder arches, 

 and as each is stiffened by a thread of bone developed in 

 its interior, while, at the same time, its sides are beset 

 with fine sharp teeth, like thorns on a brier, I suspect 

 that they play some part in crushing the life out of the 

 small animals on wdiich the herrings prey. 



Between these arches there is, in the middle line, an 

 opening which leads into the gullet. This passes back 

 into a curious conical sac which is commonly termed the 

 stomach, but which has more the character of a crop. 



