68 -KENDALL: NEW ENGLAND SALMONS. 



From outside the field of observation a third male came with a quick rush and lay along 

 the side of another male, all four salmon crowding as close together as possible over the 

 hollow bed, bodies parallel, heads on the same level and mouths wide open. The bodies 

 of the males, which remained straight in the axis of the current, were slightly turned 

 toward that of the female and were motionless except for fine muscular quivers. Suddenly 

 the water became densely clouded with the milt extruded from all three males, completely 

 masking the depositing of eggs by the female. The entire procedure was accomplished 

 within 10 seconds and the males then dropped back to their respective positions below 

 the redd. Immediately the female manifested marked activity, digging frantically to 

 cover the fertilized eggs. In the next three minutes she had eight spells of digging, 

 each time maldng from five to eight muscular "flittings" of the body and tail. 



'Fertilization for the most part takes place before the eggs reach the bottom. The 

 spermatozoa are immotUe untU they come in contact with the water, when they im- 

 mediately take on a frenzied activity, which quickly diminishes untU all movement 

 ceases within 45 seconds. Consequently, fertihzation must take place during the first 

 few seconds after the discharge. To be effective the nult should be discharged almost 

 simultaneously with the eggs, since the current rapidly carries the milt downstream 

 below the redd.' 



Respiration being as necessary to the developing embryo as to the fully developed 

 fish, suffocation of the embryo by deposits of silt is prevented by the spawning taking 

 place in running water, on a not too fine gravel bottom, where the current brings a 

 constant supply of the necessary oxygen. Among the pebbles and gravel the eggs re- 

 main (if not disturbed by predacious animals) until they hatch. In Scotland, Calderwood 

 says hatching may be expected to take place in from 90 to 100 days, in temperatures 

 varying from 40° to 45° Fahrenheit. If the water temperature is kept near 32° Fahrenheit 

 hatching is retarded for about 148 days. In eight Canadian hatcheries in the 1931-32 

 season at 35-38° Fahrenheit eggs hatched in from 120 to 192 days. Atkins beUeved that, 

 owing to the fact that in upper Penobscot waters the ice does not leave until May, the 

 eggs do not hatch earlier than that time. 



After hatching, the Uttle fish with its attached yolk-sac, which affords its nourishment 

 untU it begins to feed by the mouth, continues to grow in the recesses amongst the stones 

 for a period of about 50 days. Towards the end of this period, as the yolk-sac is ab- 

 sorbed, feeding through the mouth begins, and the fish attempts to emerge from its 

 concealment. When the yolk-sac has entirely disappeared, the fish is about an inch 

 long and adopts its free-swimming Ufe. Its habits are then influenced by its needs for 

 food and protection from enemies. The food of the fry is largely Entomostraca and small 

 insects, and larger crustaceans and insects as it increases in size. 



In Scottish rivers it is stated that the river Ufe of the yearUng salmon is two years, 

 during which period it is known as parr, which when a year old is 33^ inches long. Con- 

 cerning this phase of the Ufe history of the fish Hutton says (1924, p. 16), 'Shortly before 

 the contents of the yolk-sac are entirely absorbed, the alevin, or rather the fry, commence 

 to feed on tiny insects, I should, however, draw attention to the fact that feeding does 



