OSSEOUS FISHES. 



565 



the older individuals heading the column, the youngest bringing up 

 the rear. 



When the period for depositing their eggs approaches, a male and 

 female pair off, as it were ; seeming to choose, by a common accord, 

 a retired place in which to spawn. Here both male and female 

 employ themselves in hollowing out a nest in the strand, some eight 

 or nine inches deep, wherein the female deposits her eggs, which the 

 male fertilizes by shedding a milky fluid over them, sheltering the 

 eggs afterwards by a covering of sand. 



The salmon only ascends the rivers to spawn. They eagerly return 

 afterwards to salt water. When enjoying themselves in the water 

 they swim slowly, floating near the surface ; but in pursuit of any 

 object, or if threatened with danger, they dart out of the water with 

 extraordinary promptitude. The tail is, in fact, a true oar moved by 

 powerful muscles ; a low waterfall is to the salmon no serious ob- 

 stacle when it is impelled to ascend to its breeding-place. Curving 

 its vertebral column, it forms itself into a sort of elastic spring ; the 

 arc of which being suddenly un- 

 bent, strikes the water with great 

 force with the tail, and in the 

 rebound it leaps to the height of 

 several yards, clearing waterfalls 

 of considerable height. If it falls 

 without accomplishing its object, 

 it repeats the manoeuvre until it is 

 at last successful. It is especially 

 when the leader of the band makes 

 a successful leap that the others, ac- 

 quiring new spirit from its example, 

 throw themselves upwards until 

 their emulation is rewarded by 

 success. 



Some of the British waterfalls 

 are celebrated for their salmon leaps. 

 Wales, Scotland, and Ireland have 

 each their celebrated leaps ; in 

 Pembrokeshire, Argyleshire, and at 

 Ballyshannon, in county Donegal, and at Leixlip. The cataract of 



