186 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



AN INTENSIVE STUDY OF THE MARINE 

 PLANKTON AROUND THE SOUTH END OF 

 THE ISLE OF MAN. 



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



INTRODUCTORY. 



The objects of this detailed investigation into the 

 Plankton of a limited marine area are twofold: — 



(1) To stndy the distribution of the Plankton 

 as a whole and of its various constituents during the 

 year, and 



(2) To attempt to arrive at some estimate of the 

 representative value of such samples as are collected 

 in our plankton nets. 



Of the fundamental importance of plankton work in 

 regard to fishery questions of a wide nature there can be 

 no doubt, and of the absolute necessity of the determina- 

 tion of the value of samples and of arriving at some 

 estimation of their representative nature there can be 

 still less difference of opinion. 



In former reports* we have shown that our results 



around the Isle of Man and in other parts of the 



Irish Sea show great diversity in the plankton, 



both quantitatively and qualitatively when considered 



according to locality or according to date but in all 



these former reports we have felt that fuller information 



might enable us to reduce the apparent chaos 



to order, and might reveal some method or definite 



sequence in a distribution which seemed indefinite or 



irregular. Consequently we have endeavoured during 



the last year to make our observations as frequent, full 



* Twentieth Annual Report of the Liverpool Marine Biology Com- 

 mittee, Dec., 1906 ; Presidential Address to the Linnean Society of London, 

 May, 1907 ; and Twenty-first Annual Report of the L.M.B.C., Dec, 1907. 



