10 



has more elevated fins, larger eyes, and a lighter colored back 

 than the glut herring. 



Distribution. — The alewife is common along the Atlantic 

 coast from Canada to North Carolina. In Massachusetts 

 practically all the coastal streams were formerly frequented by 

 this fish, but as a result of the activities of man, it has been 

 exterminated in many localities. 



Reproduction. 



At the approach of the spawning season the alewife ascends 

 the tidal streams in order to deposit its spawn in fresh water, 

 a process which has become a part of the life cycle of anad- 

 romous fish, and for which no satisfactory explanation has ever 

 been offered. 



Sexes. — The ratio of males and females in the spring run 

 varies considerably, first one sex and then the other predomi- 

 nating. On the spawning grounds the usual combination is 5 to 

 (> males to 1 female, although schools of 10 to 25 males may 

 be seen following 1 or 2 females. Apparently the males greatly 

 predominate in the late runs. On June 23, 1919, as high as 

 95 per cent males were obtained in Monument River, and 98 

 per cent on the spawning grounds of Great Herring Pond. 

 Observations in May, 1920, gave the following proportion of 

 males and females during the spring run: — 



Eggs. — The eggs, averaging bHi of an inch in diameter, 

 when deposited sink to the bottom where they adhere to 

 stones, gravel, coarse sand, logs and other material. This ad- 



