286 Mr. A. T. Masterman on the Life-history 
rent the enormous outburst of larve in July or August which 
one findsin March. I think this is not insuperable. For a 
long time the eggs of the sand-eel defied ail efforts at detec- 
tion *, and it was eventually shown that the female deposited 
them in the sand below tide-mark, in water too shallow for 
the ordinary trawling-operations. These observations were 
made during the June spawning-period, and it is more than 
probable that the July and August swarms of young forms 
remain in the shallow water wpon the sand, after they have 
completed their larval period. Our laboratory attendant, 
A. Brown, who has an intelligent knowledge of the fauna of 
the Bay, tells me that in the July series the closer inshore 
one works the more abundant are the little sand-cels, whereas 
in the March series one finds the greatest number some 2 to 
1 mile seawards. 
These facts probably find their explanation in the different 
conditions of existence in the two periods of the year. In 
the calm summer months the eggs can be laid without risk 
in the sand of the shallows, where a high temperature favours 
the development, whereas in the winter months the eggs, 
laid by the parent in the sand of the deeper water, avoid all 
risk trom storms or great reduction of temperature. It may 
therefore be a simple case of the adaptation of an animal, 
guided by its instincts, to its changed surroundings. We may 
notice the same kind of phenomena in allied species, in which 
those spawning earlier in the year have a spawning-place 
further out to sea and those spawning late a spawning-place 
much nearer inshore, e. g. cod, haddock, and whiting. (See 
also ‘ Eleventh Fishery Report,’ ‘‘ Report on Pelagic Eggs.”’) 
During July and August a few forms are found at the bottom 
seawards, and they probably join the March series later in 
the surface-water away out in the offshore-water. 
The July series is shown in ‘Table II. More observations 
are required to corroborate the course of the lines; it is 
assumed that they follow much the course of the March 
series. 
We must here mention the surface-stage in the March 
series. 
The young sand-eels in May are found in the surface-water 
in millions. ‘here are before me four jars of these May 
post-larval forms, taken 15 miles off Aberdeen, Montrose, 
and Stonehaven, and their number may be estimated at 
about 50,000. 
Thus the young sand-eel forms a very important supply of 
* See Prof. M‘Intosh, ‘ Ninth Fishery Board Report.’ 
