360 transactions liverpool biological society. 



West oe Mull. 

 Hauls taken in the open sea to the west of Mull 

 always show zoo-plankton. We have three such 

 gatherings this year in the neighbourhood of the 

 Treshnish group — a vertical haul from 70 fathoms 

 between Staff a and Lunga on August 19th ; a surface 

 gathering on the same date south of Staffa ; and another 

 surface gathering a little further north, on August 22nd, 

 between the Tresnish Isles and Gometra. All consist 

 chiefly of an oceanic zoo-plankton. We print the vertical 

 haul as an example of such a gathering. None of the 

 numbers are large. Temora longicornis and Centropages 

 hamatus are neritic Copepoda, while all the rest are 

 oceanic — Candacia armata and Metridia lucens are 

 especially so, and are rarely found in the inshore waters. 

 All the Diatoms are oceanic, with the exception of 

 Rhizosolenia shrubsolei. 



Between Staffa and Lunga (Treshnish Isles). Au Vo^'homs' 



Calanus finmarchicus 700 



Pseudocalanus elongatus 10,000 



Acartia clausi 3,450 



Oithona similis 625 



Temora longicornis 300 



Centropages hamatus 300 



„ typicus 5 



Candacia armata 1 



Metridia lucens 10 



Nauplii 23,400 



Thysanoessa raschii 1 



Decapod larvae 15 



Sagitta bipunctata 36 



Plutei 625 



Gastropod larvae 1,875 



Lamellibranch larvae 1,300 



Tintinnidae 4,000 



Oikopleura dioica 300 



Medusoids 33 



Peridinium divergens 1,300 



Ceratium tripos 300 



Chaetoceras densum 27,200 



Coscinodiscus radiatus 300 



Rhizosolenia semispina , 3,450 



shrubsolei 2,500 



