152 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



only occurred once at Nelson Buoy, and then not in great 

 quantity. 



Chaetoceras boreate was common in Carnarvon Bay 

 in September, while Guinardia and Kkizo so tenia were 

 not uncommon. The same forms, with Coscinodiscus 

 and Eucampia were present at Nelson Buoy. 



October, at Station 14, shows a fresh maximum, while 

 at the other Nansen net stations diatoms were not abund- 

 ant. The most marked feature of this month was the 

 abundance of Eucampia, which was absent from Carnarvon 

 Bay, and scarce at Stations 5-7 (except Station 7 on 

 October 30th), but at some time or other abundant at all the 

 inshore stations from Red Wharf Bay northwards. This 

 form persisted on in many places well into November, 

 and was fairly abundant at Station 7 in December. 

 Eucampia is a coastal form which may be taken 

 (according to Ostenfeld) as having a flowering period 

 extending from spring to autumn, with a minimum in 

 August. In our waters it was absent in spring except at 

 Stations 5-7, while at Port Erin it was present in fair 

 numbers in May and June, practically absent in autumn. 

 It appears as if the representatives at Stations 5-7 in 

 June were derived from the Manx waters, while those 

 present at the end of the year came from our own 

 coastal waters, each area having only one marked 

 flowering period. Its complete absence from our 

 Carnarvon Bay records is rather puzzling, unless we sup- 

 pose that here, too, the flowering period was later than 

 September. On the other hand it occurred in fair 

 quantity in the south of Cardigan Bay on May 21st. 



Ceratitjm. 



This genus was present at Stations 5-7, throughout 

 the year, being commonest in summer and autumn. In 



