64 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
of 1907. The number of Diatoms does not appear to be 
so great this year as in 1907. The spring maximum does 
not reach to such a height, and is certainly much later 
than was the case last vear. Looking first at the volumes 
of the catches, the monthly average in cubic centimetres 
for the first four months of the year 1908 is as follows :-— 
January, 0°38; February, 0°6; March, 1°8; April 74; 
showing an increase in March, which became still more 
marked in April, but is small compared with that in 1907, 
The average haul during April, 1908, with the different 
nets used is :— 
Hensen. Nansen. Surface Surface Weight-net. Surface Shear. 
(No. 20). (No. 6). (Bay). 
0:6 1:42 Patel | 3°45 4:18 oO 15 
Showing much the same proportions between the nets as 
in the previous year, but smaller numbers throughout, 
In 1908, however, the catches of Diatoms continue 
relatively high throughout May and June and then drop 
rapidly in July and August. The curve for the total 
plankton seems, so far as our examination of the results 
has gone, to follow much the same course. The maxima 
in the various groups seem all to be later, and less marked, 
in 1908 than they were in 1907. 
In the summer of 1908 I took 268 gatherings in the 
sea off Port Erin in 27 days, which, with Mr. Chadwick’s 
weekly gatherings in Port Erin Bay during the remainder 
of the year, will bring the total for 1908 up to about 560, 
in addition to the samples taken by the Lancashire Sea- 
Fisheries steamer during her periodic cruises. Mr. Scott 
and I are still engaged in examining and discussing the 
summer gatherings, but so far as we have gone there 
seems no doubt that all the gatherings in 1908 were, on 
the average, smaller than in 1907, and that there was no 
marked Diatom maximum this last autumn. In 1907 
there was a marked Diatom rise during the last few days 
