NO. 5.] ACCOUNT OF THE SPECIES. 57 



The last pair of legs, on the other hand, are very different and quite 

 enormously developed, being much larger than the natatory legs, and about 

 equalling in length Vs of the whole body. The 2 legs (see PI. XIII, fig. 11), 

 as usual, are rather differently developed, both being, however, of a rather 

 complex structure, and strongly muscular. The 1st basal joints of the two legs 

 are wholly coalesced, forming a common, somewhat lamellar stalk. The 2nd 

 basal joint is rather tumid, and in the right leg considerably larger than in 

 the left. The terminal part of the former, representing the outer ramus, is 

 very much elongated, and of a rather irregular shape, consisting of 2 highly 

 chitinized pieces, movably articulated together. The proximal piece is much 

 the larger, and is curved outwards like a bow. It is very narrow, though 

 expanding somewhat in its distal part, and projecting at some distance from 

 the tip, inside, to a short, heel-shaped prominence. The distal piece has the 

 form of a narrow oblong lamella, bent in the opposite direction, and gradually 

 widening somewhat towards the tip, which is obtusely rounded. Of any inner 

 ramus, no trace is found in this leg. In the left leg, on the other hand, the 

 inner ramus is very fully developed, forming a long styliform process, nearly 

 twice as long as the outer ramus, and extending to the end of the right leg. 

 It is likewise highly chitinized and gently curved, exhibiting at some distance 

 from the tip a very slight dilatation. The outer ramus of this leg is com- 

 posed of 3 joints, of which the first 2 form together a somewhat fusiform 

 division bent inwards at the tip in a hook-like manner, and terminating in a 

 rounded lamella, finely denticulated at the edge. The terminal joint, issuing 

 outside this lamella, is very small, conical in form, and tipped with a fascicle 

 of small bristles. 



Occurrence. This peculiar Calanoid occurred in 5 of the samples, in 

 none of them, however, in any considerable number. One of the samples was 

 taken on the 12th November, 1895, near the northernmost point reached by 

 the 'Fram'. Another sample was taken on the 28th June, 1895, on the 

 very surface of the sea, all the others from depths between 100 and 300 

 metres. 



