FAMILY S A L M O N I D A. SALMONS. 



119 



ILLUSTRATIVE EXAMPLES. 



PLATE 7. 



Family SALMONS ; Salmonida. 



The Salmon family is characterised by a scaly body ; they include the 

 Salmon and Trout. They are divided into two sections, namely, Migratory 

 and Stationary. 



Genera. 



Species. 



Salmo Salar - 



Aigentina - - - - Sphyrana 



Saurus ----- Fcetens 



Family HERRINGS ; 



Clupea ----- Harengus 



Gnathobolus - - - Aculeatus. 



Porypterus - - - - Bichir. 



Common Name. 



- - - Salmon. 



- - - Argentine. 



- - - Fetid Saury. 



Clupeoida. 



- - - Herring. 



CHARACTERS OF THE GENERA. 



1. SALMO (Lat. salio, I leap). Head smooth ; mouth large ; teeth 

 conical, pointed, arming all the bones of the mouth, also the tongue and 

 branchial arches ; branchial rays ten or twelve ; body lengthy ; pectoral 

 and ventral fins of moderate size, the latter on middle of the belly, opposite 

 the true dorsal fin, and along their base a fleshy fringe ; opposite the anal 

 a spurious dorsal fin, consisting only of fat enveloped in skin ; caudal fin 

 attached to a very fleshy root. 



2. ARGENTINE. Mouth small, and toothless ; strong-hooked teeth on 

 tongue ; small teeth before the vomer ; gill-rays six. 



3. SAURUS (Gr. oWpct, a fish so called). Generic characters nearly the 

 same as Salmo. See also " Description of Species." 



1. CLUPEA. Intermaxillary bones short and narrow ; sides of jaw made 

 up of the superior maxillary bones ; gills very large, and the anterior portions 

 of the branchise towards the mouth set with fine long teeth like those of a 

 comb ; body narrow and carinated below, at which part the scales are 

 disposed like saw teeth. 



2. GNATHOBOLUS (Gr. yvadog, a jaw, and /3d\Xw, to cast). Mouth 

 vertical, closed by raising the lower jaw, opened by depressing it ; at which 

 time is protruded from the upper jaw a slightly-arched short lamina, which, 

 when the mouth is closed, recedes and rests upon the gill-covers; gill- 

 covers scaly in front, transparent posteriorly and resplendent ; head, body, 

 and tail compressed ; thorax carinated and armed with eight spines, as is 

 also the abdomen with a double row of twenty-eight ; dorsal fin small, and 

 placed far back ; anal long, and reaching to near the root of the tail ; no 

 ventrals. 



3. PORYITERUS. Head covered with sharp bony plates ; sides of upper 

 jaw immoveable ; teeth like a rasp, with long ones in front ; body covered 

 with scales ; one gill-ray ; separate fins on back ; stomach large ; double 

 air-bladder, with large lobes, the left one opening freely into the gullet. 



SALMONIDA, CLUPEOIDA. DESCRIPTION OF THE SPECIES. 



SALMO Salmon. The individuals composing this genus Salmon and 

 Trout are extremely voracious, and feed on living prey, which consists of 

 small fish, both of their own and other species, on aquatic insects and their 

 larva 3 , worms, small crustaceous animals, and the eggs of some Echino- 

 dermata. They are found in the temperate and northern parts of Europe, 

 Asia, and America, but seem to prefer the colder streams. 



All the species are extremely active in their motions, and some traverse 

 considerable distances in the performance of certain of their animal functions. 

 According to the observations of M. Agassiz, the seasons have considerable 

 influence on the colours of the individuals forming this genus, which vary 

 so much at different times as to give rise to great difficulty in denning the 

 species. The peculiar kind of food on which they live is another cause of 

 the variety of colour among the same species. 



Some of the genus are considered to be sea fish, though they cannot be 

 strictly so called, since they are spawned in fresh 'water, and only visit the 

 sea periodically for a short time ; indeed, some even of these remain con- 



stantly in rivers, being there confined accidentally. But that their annual 

 visit to the ocean is of importance to their economy, is proved by the fact 

 that fish so restrained do not thrive or acquire their usual size. Others, 

 however, are naturally located in rivers and pools of fresh running water 

 which they never leave, and are therefore strictly fresh-water fish. They 

 are all edible fish, generally of high flavour, and highly esteemed. The 

 Salmon especially is most valuable, both on account of the large quantity 

 of excellent food afforded by it, and the great number of persons engaged 

 in its capture. 



They are usually divided into two sections, the migratory or sea fish, 

 which annually visit the sea for a few months ; and the stationary or river 

 fish, which always continue in the fresh water; but, as to structure and 

 general character, there does not appear to be any material difference. 



The Illustrated Species (S. Salar), the Salmon, belongs to the Migratory 

 Section. The length of the head is one-fifth of the total length of the 

 animal ; its dorsal surface is grey or bluish-black, inclining to a lighter tint 

 on the sides ; it is sometimes spotted with black, more especially in the 

 females, and at other times plain ; the belly silvery ; the dorsal, pectoral, 

 and caudal fins blackish, the fatty fin corresponding to that part of the 

 back on which it is placed ; ventral fins white on their outer, and more or 

 less dusky on their inner surface ; anal white. 



During the summer months, Salmon are found in immense numbers 

 along the coast and at the estuaries of rivers, in which they rest a longer 

 or shorter time without any apparent reason, moving up and down with 

 the tide before they commence their regular ascent of the stream. The 

 reason of the entrance of Salmon into rivers seems to be for the purpose 

 of spawning ; and their stay at the estuaries, with frequent returns to the 

 sea, appears sufficiently accounted for by the necessity there is for the 

 animal's constitution being gradually accommodated to the great change it 

 is about to undergo in passing from salt water to fresh. This would seem 

 also to be proved by the fact that the fry and the fish which have spawned, 

 when about to return to sea, always remain for some time in the estuaries 

 before they proceed to the ocean. 



About the middle of August the milt and roe, which in May had been 

 about as large as the finger, begin to swell rapidly, and towards the end of 

 the month have attained such size as materially to diminish the quality of 

 the fish ; for, as they increase, the walls of the belly, which had previously 

 been thick, lose the fat which had been deposited there in large quantities, 

 and to such extent that little more than the skin alone is left. From this 

 time (August) the male fish is called a Kipper, and the female a Baffgit. 

 When the fish have attained this condition, they begin to ascend the rivers, 

 and continue so to do through September and October, by which time they 

 generally reach the spawning-ground. The Salmon in its ascent continues 

 its course along the banks of the rivers, preferring the shallow water, and 

 making its way over mill-dams, weirs, and up cataracts with persevering 

 resolution, often for hundreds of miles, till it has reached the proper locality. 

 During its residence in fresh water, the fish undergoes a considerable change 

 in appearance, the male becoming striped on the cheek, with orange-coloured 

 marks like a Lahrus, and the body assuming a golden- orange tint, from 

 which circumstance they are called Red-fish ; whilst the females, becoming 

 very dark, are called Black-fish. The flesh also loses colour and becomes 

 paler. For spawning they select shallow running water at the top and 

 foot of fords, where the bottom is fine and gravelly, or low down in pools 

 ,vhere the water begins to run, which assists them in moving the gravel. 



The business of spawning occupies some time, as the fish are only 

 engaged in it early in the morning or at evening twilight. They go in 

 pairs, and after playing about the ground begin to make furrows, working 

 up the gravel against the stream for a distance of about twelve feet ; into 

 this furrow they both deposit the spawn, and as it drops the gravel is 

 turned over it by the male with his tail. Having reached the extremity of 

 the furrow, they sweep round to the point at which they had commenced, 

 and passing along its side form a second, which is in like manner filled 

 with spawn, and this process is repeated till a bed of eight or ten feet in 

 width is produced. The ova or eggs are at first about the size of mustard 



