SALMON 



113 



then frequent, wounds so severe being inflicted 

 with it that death sometimes ensues. The lateral 

 line is nearly straight. The scales are small, and 

 the colour a rich bluish or greenish gray above, 

 changing to silvery-white beneath, sprinkled above 

 the lateral line with rather large black spots. The 

 opercular bones show a rounded outline at the 

 hinder edge of the gill-covers, which at once dis- 

 tinguishes this species from the only other British 

 species that can be confounded with it, the Salmon- 

 trout and the Gray or Bull Trout, in both of which 

 the posterior edge of the gill-cover is angular. The 



Fig. 3. Gray or Bull Trout (Salmo eriox). 



tail is forked in the young salmon, but becomes 

 nearly square in the adult. The mouth of the sal- 

 mon is well furnished with teeth a line of teeth 

 on each side of the upper jaw, an inner line on the 

 palatine bone, two or three in the adult state at the 

 nd of the vomer, two rows on the tongue, and one 

 row along the outer edge of eacli lower jawbone. 

 This array of teeth indicates voracity, and the sal- 

 mon seems to prey readily on almost any animal 

 which it is capable of capturing, though it is a 

 somewhat singular fact that the stomach when 

 opened is rarely found to contain the remains of 

 food of any kind. Two or three herrings of full size 

 have, however, been found in its stomach ; the 

 sand launce and other small fishes seem to consti- 

 tute part of its food, and when in fresh water the 

 minnow, trout-fry, or the fry of its own species, 

 worms, flies, &c., though there can be little 

 doubt that the salmon feeds chiefly in the sea. 

 Some hold that it does not feed in the fresh 

 water. The angler catches salmon with the arti- 

 ficial fly, or with the minnow or the worm or the 

 prawn ; and no bait is more deadly than the roe 

 of the salmon itself, the use of which is indeed 

 prohibited in British acts of parliament intended 

 lor the protection of the salmon-fisheries. The 

 eggs of crustaceans have also been found in the 

 stomach of the salmon in such quantities as to 

 show that they form a very considerable part of 

 its food. 



The salmon is found on the coasts of all the 

 northern parts of the Atlantic, and in the rivers 

 which fall into that ocean, as far south, at least, 

 as the Loire on the European side and the Hudson 

 on the American. Slight differences can be noted 

 between the salmon on the Atlantic coasts of 

 America and the European salmon, but they are 

 not generally thought sufh'jient to distinguish them 

 as species. The salmon frequenting one river are, 

 indeed, often characteristically different from those 

 of another river of the same vicinity. The Pacific 

 Salmon (see p. 116) differs in several respects from 

 the Salmo salar, particularly in its power of stand- 

 ing a higher temperature ; so that the French 

 government have recently made the experiment of 

 introducing it into some of the rivers falling into 

 tin! Mediterranean. Salmon is in perfection for 

 the table only when recently taken from the water ; 

 whilst the fatty ' curd ' remains between the flakes 

 of its flesh, which, however, begins to disappear 

 within twelve hours, although otherwise the fish is 

 Unite fresh. 



The salmon, after its first migration to the sea, 



passes a groat part of its life in it, although under 



the necessity of periodically ascending rivers, in 



which the salmon that ascend to spawn or for other 



424 



causes in autumn often remain during most of the 

 winter. Salmon return, in preference, to the same 

 rivers in which they have passed the earliest part 

 of their existence ; as appears both from records of 

 marked salmon, and from the characteristic differ- 

 ences already alluded to. Salmon ascend rivers to 

 a great distance from the sea, as the Rhine to the 

 Falls of Schaffhausen, the Elbe to Bohemia, and 

 the Yukon, the great Alaskan river, which they 

 ascend for more than 1500 miles. Salmon move 

 chiefly during the night. As a rule they do not 

 ran when rivers are low, but when they are begin- 

 ning to fall and clear after a flood. In autumn, 

 however, the sexual instinct urges them to ascend 

 to the heads of rivers where there is good spawn- 

 ing-ground and to the smallest tributaries. The 

 perpendicular height which the salmon can pass 



Fig. 4. Salmon-ladder. 



over by leaping, when there is abundance of 

 water in the river and sufficient depth in the 

 pool below the fall, seems to be not more than 6 

 or, at the utmost, 8 feet ; they attempt higher 

 leaps, but often fall back exhausted, or fall on 

 adjacent rocks, where they die or are captured. 

 They do, however, rush up steep and broken 

 rapids of much greater height. The ascent of 

 many rivers by salmon has been stopped by high 

 weirs and other obstructions ; but means have been 

 devised for preventing this by fish-stairs or fish- 

 ladders, which are often very conveniently formed 

 by partitioning off a portion of the fall, and inter- 

 secting it from alternate sides, two-thirds of its 

 width, by transverse steps of wood or stone, so as 

 partially to divide it into a succession of falls. The 

 salmon soon find out the ladder, and leap up from 

 one step to another. There are, however, very few 

 good salmon-ladders on the numerous obstructions 

 connected with mills and manufactories which have 

 been erected on salmon-rivers. The best of these 

 are the ladder at Deanston dam on the Teith, 

 at Morphie dam on the North Esk, and at Bridge- 

 mill dam on the Girvan. 



But mill-dams without fish-passes, or with in- 

 efficient passes, are not the only causes which pre- 

 vent the full utilisation of salmon -rivers. There 

 are, besides, natural obstructions, in the shape of 

 waterfalls, which at present bar 500 miles of rivers 

 in Scotland and many thousand acres of lochs 

 against the ascent of salmon. The principal of 

 these waterfalls are the Falls of Tummel, which 

 shut out salmon from 50 miles of rivers and 20,000 

 acres of lochs. They might easily be made passable 

 at a moderate cost ; but the proprietors of the falls 

 refuse their consent to have them touched ; and, as 

 the law at present stands, nothing can be done 

 without the consent of the proprietors of the 



