?)2)2 American Fisheries Society 



ments of fishes to special spawning places or the passive move- 

 ment of the eggs or larvae to waters not frequented by the 

 adults. 



Not always does nature provide the proper conditions for 

 the eggs, for the young, or for the old. During the year 1920 

 we obtained eggs of the smelt laid in the intertidal zone at the 

 head of tidal water in the Magaguadavic River, New Bruns- 

 wick, and we could not discover that any of these had developed 

 to the slightest degree, thus explaining the rarity of the fish in 

 that region. On the other hand we have the case of the floating 

 eggs of certain flatfishes and gadoids (most important commer- 

 cial fishes), which are to be found generally distributed in the 

 spring and early summer in the waters of the western archipel- 

 ago of the Bay of Fundy. We secure the eggs regularly and 

 yet we have never succeeded in obtaining any of the larvae there 

 although on other parts of our coast the latter are very abund- 

 ant and easily found. The larvae and young of the common 

 starfish are rather abundant on the gulf coast of the island of 

 Cape Breton, but during our investigations of that coast in the 

 summer of 1917 we failed to secure a single adult at any depth, 

 notwithstanding their abundance in our hauls taken at the Mag- 

 dalen Islands in the middle of the gulf. There can be no doubt 

 that the young settling on the shores of Cape Breton are fated 

 never to reach adult life. 



In the literature there have been given several reports of 

 cunners and tautog, which are nearly related warm water 

 coastal fishes, having been found killed in large numbers during 

 especially severe winter weather. Heat may be equally fatal, 

 for in the Bay of Fundy we have observed sea urchins that 

 had been caught by the spring tides in a somewhat higher 

 pool than usual and exposed to the heat of a cloudless day, dying 

 and rotting by hundreds. On the other hand, changes in salin- 

 ity may prove quickly fatal. In estuaries at the head of tide we 

 have seen specimens of the large jelly-fish, Aurelia, that had 

 been caught by some obstacle and left by the retreating tide to 

 be bathed by fresh water, perishing and disintegrating in num- 



