REVISED REPORT ON L.M.B.C. COPEPODA. 181 
COPEPODA. 
Family I.—CaLanip&. 
Calanus finmarchicus, Gunner. (Pl. XV, fig. 1.) 
Length 2.80 mm. A thoroughly pelagic species, common 
throughout the year but rarely or never taken except in 
the open sea. When found at considerable depths it is 
usually of a dark red colour and contains a quantity of 
oil. It constitutes the chief food of the Greenland whale. 
Metridia armata, Boeck. (Pl. XV, fig. 2.) 
Length 1.80 mm. Single specimens have been rarely 
found and only in the open sea at a considerable distance 
from land. The broad leafy terminations (a) of the 
swimming feet easily distinguish it. 
Pseudocalanus elongatus, Baird. (Pl. XV, fig. 3.) 
Length 1.30 mm. Very common throughout the dis- 
trict and seldom absent in any townet gathering. The 
females are often found with three or four large ova. 
Pseudocalanus armatus, Boeck. (Pl. XV, fig. 4.) 
Leneth 1.75 mm. A pair of this rare species was 
taken by surface townet in Port Erm Bay, in 1889, during 
an illumination of the surface of the sea by electric hght 
from the ‘‘ Hyena.’ Its only other occurrence in the 
district was in the “‘ Mallard” cruise of 1892 when a 
single specimen was found among some dredged material 
taken at a depth of 20 fathoms outside Port Erin. I was 
at first in doubt whether those specimens were Atidius 
armatus, Brady, and after careful examination of them 
with Brady’s description of the latter, I am disposed to 
query whether the two species are not synonymous. The 
lateral spines of the posterior end of the cephalothorax 
readily distinguish it from P. elongatus. 
Paracalanus parvus, Claus. (Pl. XV, fig. 5.) 
Length 1.30mm. One specimen only of this rare form 
was taken by townet off Puffin Island. 
