136 BRITISH COPEPODA. 
3-setose; outer narrow, quadrate, armed with one 
long, and four short, terminal sete. Length 34th of 
an inch (1:05 mm.). | 
This is very similar in many respects to the following 
species (7. longimana); but, besides the less gibbous 
outline, less vivid colouring and more delicate skin, it 
differs considerably in several anatomical points, 
especially in the structure of the fifth pair of feet in 
both sexes, and the inner branch of the fifth pair in the 
male. T'he posterior foot-jaw, though similar in general 
character to that of 7. longumana, is much less robust 
and less angular. T'. hibernica was taken very spar- 
ingly in the tow-net in Westport Bay (Ireland) and 
rather more plentifully m a gathering off Cumbrae 
(Firth of Clyde). Oban (fev. A. Norman). 
9. 'THALESTRIS LONGIMANA, Claus. Pl. LX, figs. 1—13. 
Thalestris longimana, Claus. Die frei-lebenden Copepoden, 
p. 180, t. xviii, figs. 1—11 (1863). 
Body very robust, cephalothorax much arched 
dorsally, integument thick and tough, rostrum broad 
and blunt, body-segments bordered with chitinous 
marginal bands, which are often deeply coloured, 
brownish or blood-red, the general colour of the 
animal being yellowish. Anterior antenne (figs. 2, 3) 
9-jointed, joints of the peduncle long and stout, those of 
the flagellum short; inner branch of the posterior an- 
tenna (fig. 4) 2-jomted, short ; mandible (fig. 5) strong, 
with a large, well-developed palp ; maxilla (fig. 6) 
