FISHES OF THE GULF OF MAINE 



519 



Tracy (1910, p. 166), the fry are 2 to 3 inches long in July and 4 inches and upward 

 in December. Measurements made by Welsh off the New Jersey coast indicated 

 an average length of about 6 to 9 inches by the end of the second summer and 10 

 to 12 inches the third summer when the fish are mature. 



Migrations. — Owing to the brevity of its pelagic stage, already remarked (p. 518) , 

 its involuntary downstream migrations are necessarily short and consequently the 

 chance of dispersal by this means is slight. As there is no reason to suppose that 



Fig. 269.— Larva, 5.5 millimeters 



"wimp,- 



"^ 





Fig. 270.— Larva, about 8 millimeters 

 SAND FLOUNDER (Lophopsetta maculata) 



it wanders any more than do the winter flounder, dab, or witch, when adult, it is 

 perhaps the most stationary of all Gulf of Maine flounders. 



Effect of temperature. — Occuring over so wide a range of latitude, and in shallow 

 water exposed to the extremes of winter chilling and summer warming, the adult 

 sand flounder necessarily exists in the widest range of temperature. In winter its 

 native bays are close to the freezing point in the northern part of its range, and 

 probably the entire stock in the Gulf of Maine winters in water colder than 36°, 

 while these same fish summer in temperatures of 50° to 70°, according to exact 

 102274—251 34 



