OBSERVATIONS IN THE INTERMEDIATE REGION 3" 



which is mainly ice-free throughout the year. It was most frequently observed in 

 December 1938, rarely earlier in the year, our earliest record being in September. We 

 have already had occasion to remark that 1938-9 seems to have been an unusually 

 heavy ice year, and it may well be that the heaviest incidence of Phaeocystis in the 

 Northern Region is normally somewhat earlier. Phaeocystis has not been observed 

 later in the season than December at any time in the Northern Region. At the time of its 

 maximum importance it was present at only nine out of thirty-two stations and abundant 

 at only three of these. 



THE INTERMEDIATE REGION 

 As one would expect, it was not possible to obtain many winter observations in the 

 Intermediate Region, but there is no doubt that the pigment values are minimal at that 

 time. Although it was necessary to consider results from different seasons together, 

 the large number of observations for most months that are available renders the mean 

 figures given in Table 4 and graphically in Fig. 1 1 fairly conclusive, and there seems 



Table 4 



1500 



1000 



500 



[I] 



Julu August September October 'November' December JanuarLj Februaoj March April 



Mau 



June 



Fig. II. Intermediate Region. Annual variation in plant pigments per m.^ means of all available obser- 

 vations at mean dates. Numbers of observations shown in brackets. 



7-2 



