SEA-FISHERIES LABORATORY. 303 
It is quite possible, considering the small bulk of 
the catches and the difficulty of measuring them exactly, 
that these resemblances are merely coincidences, and 
have no real value. We propose, however, to make some 
further observations by this method in the hope that if 
a relation can be established between the plankton in 
the known volume of pumped water and that in our nets, 
it may afford a clue to the amount of water that has 
passed through the towed surface nets. 
We hope also to make some observations during the 
coming year with the ‘‘ Pump and Filter’’ methods of 
Lohmann. 
CONCLUSIONS. 
The most noteworthy fact that is made known as the 
result of this year’s work is that 1910 in general 
resembles 1907 more than the intervening years. For 
the total plankton the highest monthly average was in 
April in 1907 and in 1910, and in May in 1908 and 1909. 
Again the individual hauls at the time of the spring 
phyto-plankton are much greater in 1907 and in 1910— 
in brief, the Diatoms appeared at an earlier date and in 
greater abundance in these two years than in 1908 and 
1909. We have some evidence to show that there was 
also a similarity in the hydrographic conditions and in 
the sunshine records of 1907 and 1910, which may 
possibly be connected with the plankton variations. 
We have shown that the spring and early summer 
Diatom maximum can be resolved very distinctly this 
year, and probably in other years also, into an April 
series and a June series, and that these are formed of 
distinct species, those in April being species of Chaeto- 
