104 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



AN INTENSIVE STUDY OF THE MARINE 

 PLANKTON AROUND THE SOUTH END OF 

 THE ISLE OF MAN.— PART X. 



By W. A. Herdman, F.R.S., Andrew Scott, A.L.S., 

 and H. Mabel Lewis, B.A. 



[abstract only.] 



We have noAv completed ten years of this intensive study 

 of the plankton of a small area near the centre of the Irish Sea. 

 Had times been normal we should now have drawn up and 

 submitted to the Committee a comprehensive report upon 

 the ten years' work, with a discussion of such conclusions as 

 we have arrived at. Under present conditions, however, this 

 is impossible ; so we retain our sheets of data, tables, curves 

 and other results in the hope that we may be enabled to discuss 

 and publish them on some future occasion, and must be content 

 now to record a mere outline of the past year's work on similar 

 lines to the statement given in our last report. 



During 1916 we have been enabled to collect 496 samples, 

 which, added to the 4,620 of the previous nine years, gives us 

 5,116 in all — well over the 5,000 samples which we had desired 

 to work with. Of the nearly 500 samples of the past year 

 286 were taken regularly week by week throughout the year 

 by the staff of the Port Erin Biological Station, and 210 were 

 special gatherings taken by Professor Herdman from a motor 

 boat during April, August, and September. Well over 20 

 (24 or 27) official gatherings were taken in each month, except 

 January (15) and October (14) when the weather was excep- 

 tionally bad at sea. 



The spring maximum for the total plankton in 1916 was 

 in June, a month later than in 1915 and several previous 



