204 



ICHTHYOLOGY 



Malacop. a lengthened form, the body covered with scales of no 

 terypii great size, and furnished with two dorsal fins. The first 

 dorsal fin is composed of soft rays ; the second, gene- 

 rally of a fatty substance, resembling a fold of the skin, 

 is usually of small size. The tail is remarkably power- 

 ful, acting as an elastic lever, and, as usual, constitutes 

 the principal organ of locomotion. Tlie margins of the 

 jaws are formed by the maxillary and inter-maxillary 

 bones, and, with the vomer and palate bones, are com- 

 monly thickly studded with teeth, strong, conical, and 

 bending backwards. The maxillary and inter-maxillary 

 bones constitute a single continuous arch, as in the higher 

 animals. The pyloric portion of the stomach is furnished 

 with numerous appendices connected with a pancreas. The 

 swimming bladder is large and oblong, and opens into the 

 gullet near the extremity. They are voracious, feed on 

 insects, the less Crustacea, and small fishes. Many of the 

 species are migratory, and approach the mouths of rivers, 

 or ascend their streams for the purpose of spawning. In 

 the breeding season they are marked by some appendage 

 peculiar to the time, or by a change to colouring of more 

 brilliant tints. They reach a large size. The flesh is well 

 flavoured and wholesome. 



In the modern arrangement it was found necessary to 

 separate the Salmonid.je into groups ; and in the present 

 sketch we shall follow those proposed or adopted by Ba- 

 ron Cuvier in the last edition of the Ri'gne Animal, — 

 having deeply to regret that his decease should have pre- 

 vented his great ichthyological work from advancing to a 

 branch of the subject which still stands in need of revi- 

 sion, and which would undoubtedly have derived the most 

 signal advantage from the exercise of his critical skill. 



Genus Salmo, Cuv. Edges of the upper jaws form- 

 ed by the maxillary and inter-maxillary bones, which, 

 with the palatine bones, vomer, and tongue, are armed 

 with strong conical recurved teeth ; rays of the gill-covers 

 from ten to twelve ; tail very powerful ; posterior dorsal 

 fin adipose ; ventral fins ])laced opposite the anterior dor- 

 sal, anal opposite the posterior ; vertebroe from fifty-six to 

 sixty. The male fish has the nose elongated and the un- 

 der jaw hooked during the breeding season. The silvery 

 colours change to gray and red. The species inhabit the 

 sea and fresh waters. Some migrate at the breeding sea- 

 son ; all spawn in shallow streams, and both sexes assist 

 in forming the spawning bed. They inhabit Europe, Asia, 

 and America. 



The fishes which constitute this genus are of great im- 

 portance, and are by far the most esteemed and valuable 

 of all those which inhabit the fresh waters. The value of 

 the fisheries, with the number of men engaged in them, 

 is very great, and the expense of the materials which are 

 consumed in the capture of one or two species is immense. 

 In Britain they are mostly consumed in the great towns, 

 either in a recent or prepared condition. In the north 

 of Europe and America numbers are salted or otherwise 

 cured for exportation. At the commencement of the ge- 

 nus is generally placed 



Salmo salar, or common salmon, a species which likewise 

 occupies the foremost place in the estimation of both sports- 

 man and epicure. The salmon is a fish of great elegance, 

 combining a form fitted alike for strength and swiftness ; 

 and its depth and thickness, while in good condition, are so 

 proportioned to its length as at once to convey the idea of a 

 pleasing symmetry. The body above is of a rich bluish or 

 greenish gray, changing below to silvery, sprinkled above 

 the lateral line with rather large sub-cruciform black spots, 

 a few of which at the shoulders generally extend below the 

 line. The characters which distinguish it from its British 

 congeners are the diflerent form of the opercular bones, 

 which show a rounded outline to the posterior edge of the 

 gill-covers, the longest diameter of which to the nose would 



be in a line through the eye, while in all the other British Malacop- 

 migratory species the same line would pass much below the ter.vg" 

 eye. The black inner surface of the pectoral fin is nearly ■'^bdoini- 

 a constant mark. The tail is forked in the young state, but 

 fills up to a nearly square outline in the adult, in which 

 the width between the extremities is proportionally wider 

 than in S. eriox, the only migratory species which attains 

 a weight at all approaching that of the salmon. The out- 

 line of the scales also presents distinguishable differences. 



The common salmon inhabits the seas around Great 

 Britain, and extends to the north of Europe and to Asia; 

 but it is not properly ascertained that those found in 

 North America are identical. Its true abode may be 

 called the sea; for as soon as it has entered the rivers 

 it begins to deteriorate in condition, the scales lose their 

 brilliant silvery lustre, and the flesh becomes soft and pale. 

 It is drawn to the fresh waters by that natural instinct so 

 wisely implanted for the purpose of its reproduction, an 

 instinct which enables it to stem the current of the most 

 rapid rivers, to ascend precipitous falls, and to pass through 

 weirs and obstacles of human intervention, which no other 

 power could overcome. This desire of looking for a suit- 

 able place in which to deposit their ova is their sole rea- 

 son for thus seeking the " rivers of water," the torment 

 of sea insects, or other causes which have been assigned, 

 having no influence. This may be at once understood 

 from the fact of the barren fish continuing their usual 

 haunts along the coast, while a great many do not for a 

 year at all enter the fresh waters. It is during this run 

 to the proper spawning beds that the greatest numbers are 

 captured, either by weirs, cruives, nets, or the rod; and it 

 is then also that tlie sporting angler alone can ply his vo- 

 cation, almost all attempts to angle the salmon in salt wa- 

 ter having yet proved unsuccessful. Many fish far ad- 

 vanced with spawn are by these means destroyed; for 

 unfortunately the most advanced are the most voracious, 

 and a needy fisherman looks more to his present gain than 

 to an expected produce of another year. It would be 

 well and wise if the net fisheries of tliis valuable species 

 were more confined to the tide-ways, where, in some es- 

 tuaries, they are extensively carried on (as well as in the 

 rivers) by means of stake-nets. These are so constructed 

 as to intercept the fish entering the rivers, all in a high 

 state of condition, and are sometimes wrought to such 

 an extent as to employ several miles of netting. 



Salmon generally delay entering the rivers in great num- 

 bers until the streams become somewhat swollen by rains, 

 although in the larger rivers there may be said to be a 

 limited daily run. When the flood has fairly mingled with, 

 and to a certain extent has saturated, the estuaries, the rush 

 of fish is often very great, especially if there has been a 

 continued tract of dry weather. In the latter case they 

 collect at the mouths of rivers, and are seen and often 

 taken in vast numbers ; but they do not then attempt an 

 ascent, deterred perhaps by the clearness of the stream, or 

 by some instinctive feeling that the water would yet be de- 

 ficient to carry them through. As the fiesh approaches, how- 

 ever, an increased activity may be perceived ; and, as far as 

 we can judge, the change is probably indicated by the nostrils 

 receiving a sense of the mixture of the waters, by means of 

 the large ramification of nerves with which they are supplied; 

 and to this same sense may perhaps be attributed the singu- 

 lar fact of the greater proportion of salmon returning to the 

 ^ ery streams in which they were spawned. The fish, on en- 

 tering the river, rush forward as long as the flood continues, 

 seldom resting in their course during the time that the water 

 continues discoloured. From ten to twenty-five miles daily 

 is the rate, as far as can be ascertained, at which they are 

 supposed to travel. 



In their more lengthened courses, where the rivers are 

 deeper and the interruptions less frequent, the rate at 



