450 
BULLETIN OF THE BUREAU OF FISHERIES 
of an eastward expansion of its flowering area; and although the waters farther east 
along the coast supported only a scattering of Thalassiosira on the 12th (station 20099, 
April 12), it is probable that this genus is flowering actively all along the northern 
the years 1913 and 1920 
shores of the gulf by the middle of the month in most years. It is also likely that 
the harbors and bays along this part of the coast see a great production of Thalas- 
siosira commencing a week or two earlier, judging from conditions at St. Andrews. 
