52 



THE AQUARIUM, JULY, 1893. 



does this by digging at the gravel on 

 the bottom, all the while fanning 

 away with the fins the mud and finer 

 sand, thus cleansing the gravel that is 

 subsequently to be used to cover and 

 protect the deposit. The spawn is not 

 all deposited at once, a portion being 

 extruded at intervals, each deposition 

 then carefully covered with gravel. 

 During this time the male stands guard 

 against intruders, though he himself 

 cannot resist the temptation to devour 

 any stray eggs that have been over- 

 looked by the female. The weight of 

 the eggs is sufficient to sink them, and 

 in addition they are covered with some 

 glutinous or adhesive substance. These 

 two properties are evidently for the 

 purpose of preventing their being washed 

 away by the stream until covered with 

 gravel by the parent fish. On the 

 average each female deposits about 10,- 

 000 eggs, each of the size of a currant 

 berry ; out of these, it is estimated, 

 about five per cent, develop to a full 

 sized salmon. The act of spawning, as 

 above described, may continue through- 

 out several days, and when completed 

 the fish are weak and unfit for the 

 table. They now slowly make their 

 way to deeper water, and when ice 

 covers the river they go on to the ocean 

 to regain strength. 



The eggs are hatched after a period 

 of incubation varying from 45 to 140 

 days, according to the temperature of 

 the water. For the first four or six 

 weeks the young derive nourishment 

 from the yolk-bag. The fully devel- 

 oped young are of a light brown color, 

 and marked with some nine or ten dark 

 cross-bars. Although hatched in rap- 

 idly running water, they prefer at this 

 age to remain in quiet, shallow water, 

 and where, if need be, they can find 

 shelter and protection among the stones. 



When about a year old, say in May or 

 June, the strongest, which then meas- 

 ure three or four inches in length, 

 change color, assuming a brilliant silver 

 tint. They gather together in shoals, 

 and go down stream to the ocean, re- 

 maining there for from one to three 

 years, at the end of that time return- 

 ing to the river. 



The weaker of the newly-hatched 

 young remain in the river until the 

 succeeding year before the journey to 

 the ocean is made. 



Once in the ocean, the young salmon 

 grow at a wonderful rate ; marked 

 specimens having been caught eight 

 weeks after were found to have attained 

 a weight varying from two to five 

 pounds. Under favorable circumstan- 

 ces the salmon will in the lapse of twa 

 years' time acquire a weight of twenty- 

 two pounds. 



The food upon which the salmon sub- 

 sists and thrives, consists of the vari- 

 ous kinds of Crustacea, so abundant in 

 salt water. This rich and nutritious, 

 aliment gives to the fish the color and 

 exquisite flavor that so delights the 

 palate of the gourmand. The flavor, 

 however, will vary according to the 

 locality in which the fish is reared 

 and the quality of food consumed. 

 As an instance of this, the smoked 

 salmon from the Rhine yields just 

 double the jirice per pound than 

 that from the river Wesser (Ger- 

 many). 



Throughout the various stages of 

 growth the fish is known by several 

 names ; during the first year it is called 

 " parr," while on the first trip to the 

 sea it is known as " smolt," on the first 

 return to the river, "grilse." The 

 name "salmon" is given to it at the 

 age of three years and when it is ready 

 to spawn. 



