COPEPODA. 43 



more than one quarter as long as Ri 1. Rel elongated and seven or eight times as 

 long as broad. 



Anterior foot jaws with a rather stout, but unarmed hook on the fifth lobe, not 

 longer, however, than the other bristles. 



Posterior foot jaws thick, with Ri of similar thickness to B 2, and of five 

 segments ; the five stout curved hook bristles of nearly equal length, the two terminal 

 only a little the longest and thickest. 



Mandibles with Ri very long and Re only as long as Ri 1 ; masticatory plate with 

 outer stout, broad-based, conical and curved tooth ; three pointed short teeth internal 

 to it, rather like H. mucronatus. 



Maxillae. — First inner lobe with six bristles, ot which only two of the distal ones 

 are stout hooks ; second inner lobe with one stout long bristle ; third inner lobe with 

 one stout elongated and two short thin bristles ; £ 2 about as broad as long, with four 

 elongated and thick bristles and one thin, short proximal bristle, Ri longer than broad, 

 and about three-quarters as long a,s B2 and only half its width, and with five bristles ; 

 Re very long, twice as long as Ri + B2, and nearly twice as long as broad, with eleven 

 bristles, of which the three innermost are short and thin. 



All feet with three jointed rami. Re of fifth pair only five-sevenths as long as Re 

 of fourth pair ; Ri of fifth pair only as long sls Re 1+2 ; Re S longer than Re 1-1-2, 

 twice as long as broad, with three inner bristles, two outer spines, and end spine nearly 

 as long as the last segment. I have not yet seen the 3 of this species. 



OITHONA (Baird). 



Two species of this genus occur in these collections, one of which, viz., Oithona 

 similis, is of world-wide distribution, and occurs with great frequency in Antarctic 

 collections ; the other, to which the name Oitliona frigida has been given by 

 Giesbrecht (and which has been fully described by him in the ' Belgica ' report, vide 

 ante), occurs very sparingly in the ' Discovery ' collection. 



HARPACTICUS (Dana). 

 Harpacticus puroifer. 

 Harpacticus furcifer, Giesbrecht, ' Belgica ' Report, p. 37. 



The ? of this species was first described by Giesbrecht in the ' Belgica ' report ; 

 and in the 'Discovery' collection, marked 4. i. 02. W.Q., occurred three specimens of 

 the male, though female examples were conspicuously absent. 



The ?, according to Giesbrecht, is 1-55 mm. long; the rostrum small, the 

 series of points on the abdominal segments not numerous, the furca as long as both last 

 abdominal segments, narrowing distally and about three times as long as broad ; the 



p 



VOIi. IV. 



