451 



Variation in colour and form as well as size is to be observed. From rapid 

 streams the trout are lithe and long-finned, from quiet lakes rounder and short- 

 finned, while from cool brooks the most vividly coloured individuals are obtained, 

 and from dark pools those with sombre hues. 



The food of the brook trout is chiefly formed of insects and insect larvae 

 (mosquito and black-fly larvae among the number) it is therefore not surprising 

 that, with the cultivation of the country and the consequent reduction of breed- 

 ing places for flies, the trout should have become scarcer as well as the food. 



Like the salmon, the Brook Trout seeks gravelly bottoms in streams to deposit 

 the spawn in the fall of the year, the season lasting from three to six months. 

 The female excavates a nest in the gravel, fans out the sand by means of the 

 anal fin, the male keeping watch while this operation is in progress. The eggs 

 are three-sixteenths of an inch in diameter, varying, however, considerably in 

 size and in number with the weight of the fish. A one pound trout has furnished 

 1,800, but the numbers are not proportionately large for the bigger fish on account 

 of the larger size of the eggs in these. 



The amount of time which the eggs take to hatch is a question of tempera- 

 ture. Fifty days in water of 50F. is an experiment of the hatching house, but 

 this may be diminished to thirty-two days in water of 54?, and prolonged to one 

 hundred and sixty-five days in water of 37. The last condition is that which 

 obtains in nature. The yolk-sac is absorbed in another month or two after 

 hatching, when the independent life of the young trout begins. 



The only remaining physostomous fishes of economical importance are the 

 members of the' pike family (the ESOCID.E.) In passing to them, however, refer- 

 ence may ba made to certain inconspicuous forms which properly belong here. 

 The first is the trout-perch (Percopsis gudtatus), a little fish of six inches in length 

 combining the characters of the fish named. It has a small adipose fin, ten pyloric 

 coesa, and its mouth is more like that of a perch than of a salmonoid. It spawns 

 in spring. 



A second group is formed by various minnow-like fish such as the spring min- 

 now, Fundulus diaphanus, a member of the family Cyprinodontidse, resembling 

 the minnows in their protractile jaws, but differing from them in their being for the 

 most part brackish water fish, and of ovoviviparous habit. The mud-minnows, 

 (Umbra limi) which are everywhere abundant in ditches, resemble the foregoing 

 in their habits, but are more like miniature pike in structure. . 



The members of the pike family (Esocidse) are characterized by an elongated 

 body with prolonged and depressed snout. The mouth is adapted by iits 

 wide gape and its formidable armature of teeth to the voracious habits of the fish. 

 The dorjal fin is far back over the anal in all, and there is no adipose fin. All 

 belong to the genus Esox, which includes some lesser pike confined to the States- 

 (there called pickerel), and the two species that are common in Ontario, ''JK. 

 Indus, the common pike Indian Kenosha (French rendering Kinonge") and E. 

 nobilior, the great pike or maskinonge. 



These species may be distinguished from each other by the circumstance that 

 in the pike, E. Lucius, the cheeks are scaly, the gill-covers bare, while in the 

 maskinonge the lower halves of the cheeks as well as the gill-covers are destitute 

 of scales. The branchiostegal rays also are 14 to 16 in the pike, 17 to 19 in "' the 

 maskinonge", while the colouration of ths former species is light spotted on a dark 

 ground, of the latter, dark spotted on a light ground. 



The pike propsr is cornmm to both sides of the Atlantic; the rriaskinonge' is 

 confined to the basin of the St. Lawrence. Both sp3cies spiwn in spring, the 



