172 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



illustrated in the results obtained from collections made 

 in Port Erin Bay on September 25th, 26th, 27th and 

 on October 4th. 



Sept, 25-27. Oct. 4. 



Biddulphia r. ... v.r. 



Cliaetoceros ab. ... v.r. 



Coscinodisciis r. ... v.r. 



Rhizosolenia fr. ... v.r. 



Ceratium tripos fr. ... r. 



Pleurobrachia .' r. 



Sagitta o. ... r. 



Copepoda c. ... v.ab. 



Calarms r. ... r 



Pseudocalanus fr. . . c. 



Paracalanus fr. ... e. 



Teinora fr ... fr. 



Acartia c. ... o. 



Oithona fr. ... o. 



Oikopleura fr. ... r. 



Quantity of Material 25 <;.c ... 12 c.o. 



On September 25th the sea water was filled with 

 Diatoms, chiefly Chcetoceros. Sagitta were tolerably 

 common, Copepoda w T ere fairly numerous, the most 

 plentiful being Acartia. During the next two days 

 similar conditions prevailed, not only in Port Erin Bay 

 itself, but in all the outer area from Bradda Head to Bay 

 Fine. On October 4th, just a week later, the conditions 

 had completely changed. Diatoms had almost vanished, 

 only a few individuals belonging to the genera mentioned 

 were found. Copej)oda had, however, become extremely 

 abundant. Pseudocalanus, Paracalanus, Acartia, and 

 Oithona all being tolerably common. The water was less 

 densely populated with organisms on October 4th than 

 between September 25th and 27th. 



The table opposite gives the results obtained from 

 the tow-nettings taken in the vicinity of Port Erin from 



