256 



TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY 



We are indebted to Mr. Chadwick for much help at 

 the Port Erin Biological Station ; to Mr. Riddell for his 

 assistance in the Liverpool Laboratory in analysing, 

 comparing and discussing- the results of the many hauls 

 taken during the year; and to Miss Lewis for the 

 numerous statistical lists, tables of occurrence and curves 

 which she has drawn up. Mr. Eiddell and Miss Lewis 

 have been most helpful during the writing out of this 

 report, and have saved me much time by preparing 

 the material for me to consider and discuss. — 



W. A. Herdman.] 



INTRODUCTION. 



We shall first under this heading give an account of 

 how the work was carried out in 1909. Then will follow 

 a section on the hydrographic conditions off Port Erin. 

 Finally, the planktonic results will be discussed in detail. 



The Material Available. 



The collections made this year have been more 

 numerous than in either of the previous years, but for the 

 most part fall into the same series of samples, and are 

 therefore directly comparable with those of '07 and '08. 

 The total number of samples now examined in this 

 intensive study of a small marine area is nearly 2,000, 

 made up as follows : — 



Year. 



At Sea, from Yacht. 

 Spring. Autumn. 



In Bay 



throughout 

 Year. 



Mr. 



Dakin's 

 hauls. 



Totals. 



1907 

 1908 

 1909 



218 

 156 

 329 



279 

 242 

 147 



138 

 157 

 231 





1, 



635 

 555 

 756 



Totals 



703 



668 



526 



+ 



49 



1,946 



