MARINE BIOLOGICAL STATION AT PORT ERIN. 



63 



April 28— May 14 

 May 15 — onwards 

 August (parts of) 

 Set>t. 14— Nov. 9 

 Nov. 10—14 

 Nov. 15—16 

 Nov. 17 

 Nov. 18—20 

 Nov. 21—30 



Neither 



Amphidiniurn (more or less) 



Neither 



Amphidinium 



Neither 



Amphidinium (small patches) 



None 



Amphidinium (several large patches) 



Traces and small patches only 



Now another curious point — in all the recent 

 gatherings, since September 14th, 1912, the individuals 

 are found to differ considerably in shape, size, and some 

 other minor points, from the Amphidinium operculatum 



Fig. 9. Amphidinium operculatum, larger, elongated form prevalent at Port Erin 

 in the autumn of 1912 : b and i show intermediate characters ; m and n are 

 seen edgeways ; h is an optical section to show that the pigment is peripheral 

 leaving a clear centre ; g is probably an immature stage. 



we had been examining in such quantity at Port Erin 

 during the preceding year. The new form (see fig. 9), 

 while agreeing more closely with the genus Amphidinium 



