60 



ISOPODS AND AMPHIPODS. 



The only species of Isopods found in the catches were Idotea 

 balthica (Pallas) at station 1 in May, June and October, and Eurydice 

 pulchra, Leach, at station 5 in July. 



The commonest of the Amphipods was Euthemisto compressa 

 (Goes). Apherusa borealis (Boeck), Apherusa bispinosa (Bate), and 

 a juvenile Metopa were also taken. 



Copepods. 



Copepods were most abundant in the months June to Septem- 

 ber, but in May they were present in large numbers at stations 7 

 and 8, and in October at station 7. The commonest forms and 

 those forming the bulk of the catches were Pseudocalanus elongatus, 

 Boeck, and Acartia clausi, Giesbrecht. 



Juvenile forms were taken in the largest numbers in May and 

 June, and again in September, though in the latter month there 

 were few juvenile forms from stations 7 and 8. 



Calanus helgolandicus (Claus) was found in all months, but not 

 at every station. It was generally most abundant in the offshore 

 waters, and was taken only in small numbers in August and Sept- 

 ember. 



Pseudocalanus elongatus, Boeck. One of the commonest of 

 our copepods. It occurred only sparingly in May ; in June it was 

 more plentiful in the northern part of the district, whilst in July, 

 August and September it formed the greater part of the catches. 



Centropages typicus, Kroyer. It was only in September that 

 this species was taken in any quantity, and then in the offshore 

 waters. One or two occurred in June in the catch from station 8, 

 none in July, few in August from stations 1 and 8, and in October 

 it was present, but in small numbers, in all catches. 



Centropages hamatus (Lilljeborg). This species though rarely 

 occurring in any great numbers was commoner than the preceding, 

 and was taken every month, being most abundant in July. 



Temora longicornis, Miiller, was taken in greatest numbers in 

 the inshore waters of the northern part of the district in September. 

 It was found every month. 



Anomalocera pater soni, Templeton. Was most abundant in the 

 offshore waters. It was fairly plentiful in May at stations 7 and 8, 

 and again in September at station 7, in which month it was more 



