Or 
— 
SEA-FISITERIES LABORATORY. y} 
THE INFLUENCE or PREVALENT WIANps. 
Tt was shown long ago by Sir John Murray on the 
West Coast of Scotland that the prevailing winds, 
especially if they blow on or oft shore for a few days at a 
time, have a strong effect upon the temperature and other 
characters of the water—driving the surface layer along 
and allowing deeper layers, which may be of different 
character, to appear or the surface behind. As the layers 
from different depths may be characterised by different 
types and quantities of plankton, it is evident that the 
plankton catch day by day on the surface at one spot may 
be influenced by the direction and intensity of the wind. 
Consequently it may be worth enquiring whether any 
relation can be established between the varying plankton 
catches and the weather records at Port Erin. 
’ For the last fifteen years weekly forms recording the 
weather have been filled up by the Curator of the 
Biological Station, and for the last six years records of 
the sea and air temperature and of the weather have been 
made for the Meteorological Office, London. On these 
forms the direction of the wind is entered twice daily, at 
9 am. and 3 p.m., with such a rough indication of the 
intensity as is given by the words “light,” ‘ fresh,” 
Pctrone, and “gal .” 
We have assigned the values 1, 2, 3 and 4 respectively 
to these four terms, and in distributing the numbers of 
the records and their values between the sixteen points 
of the compass we get the results for the months of 1907 
and 1908 which are shown in the accompanying tables 
and diagrams.* 
* For which we are indebted to George W. Herdman, B.Sc., who has 
kindly analysed and summarised the daily records and has constructed the 
diagrams. 
