SEA-FISHERIES LABORATORY. 149 



Station 5, accompanied by a sudden maximum of 

 Thalassiosira nordenskioldii and Nitzschia seriata. At 

 Station 7 the most of this maximum is due to Lauderia, 

 Eucampia,' and Thalassiosira. At Station 5 the Uhizoso- 

 lenia maximum seems to have occurred at the same time, 

 but at 6 and 7, it occurred later, in July, and is 

 accompanied by Guinardia. It may also be noted that 

 Chaetoceras schuttii, which at Station 14 occurred only in 

 October, is here found only in April and May. 



Biddulphia does not show any well-marked maxi- 

 mum, but was most abundant from March until May, and 

 again from October to December. 



There does not seem to be anything which could be 

 called an autumn maximum; diatoms on the whole are 

 scarce after July. 



It is interesting to note that Ditylium, which is 

 typically an autumn form, is here commonest in May 

 and June, though at Station 14 it seems to have had more 

 or less its normal distribution. 



There is no trace in any of my samples of the sudden 

 enormous development of Asterionella, which occurred at 

 Port Erin this year. 



Ceratium appears to have been commonest in June 

 and July, but never in very great quantities. The two 

 species, C. longipes and C. intermedium, seem to be 

 mutually exclusive, C . intermedium occurring mainly in 

 summer and autumn, C. longipes at the beginning and 

 end of the year. 



On the whole Station 5 seems to be the richest of the 

 three, especially in zooplankton and Chaetoceras. The 

 other diatoms, except Thalassiosira, are more abundant 

 at 6 and 7, Eucampia and Lauderia especial ly being most 

 abundant at 7, and also Guinardia. 



In the Ked Wharf Bay area (Table III), the course of 



