164 ZOOLOGY. 



laid in shallow holes made in the gravel of streams. The 

 extreme young is banded and called parr; when about a 

 year old, and of a bright silvery color, before descending 

 the rivers to the sea, it is called a smolf; after its return 

 from the sea into fresh water it goes by the name of grilse; 

 and finally, after returning a second time from the sea, it 

 assumes its name of salmon. The trout {Sahno fontinalis) 

 also breeds in the autumn and early winter; it is not mi- 

 gratory, living permanently in streams and ponds. 



An allied family embraces the smelt (Fig. 207). The 

 capelin [Mallotus viUosus) is valuable as bait in the cod 

 fishery. It spawns in the summer. The males are distin- 



FiG. 207.^rhe Smelt, Osmerus mordax", one half natural size. 



guished by a prominent lateral ridge along the sides of the 

 body, and are more numerous than the females. 



Tlie carps {Oypriinis), shiners, and minnows abound 

 everywhere in the Northern States in ponds and weedy 

 r.treams. The breeding habits of the dace {SliinicJithys 

 atronasus) are interesting. The females spawn over " nests" 

 or shallow depressions two feet in diameter in running 

 brooks about a foot deep; the male passes over the eggs fer- 

 tilizing them; then the pair bring small pebbles which are 

 dropped over the eggs, until layer after layer alternately of 

 eggs and pebbles are deposited, when a heap is formed, the 

 young hatching out and remaining among the pebbles until 

 old enough to venture out into the stream. The dace is 

 closely allied to the chub {Scmotilus rJtoiheus, Fig. 209). 



