AMPRIPODA. 37 



The most noticeable character of thia species is (as the name implies), the flMtt 

 length of the lower antenna), especially in the male. 



FAM. SEBID/E. NOV. 



Rudy rather slender, suUlepresscd ; side-plates moderately deep. 



Antenna subequal, rather short 



Mandibles with a toothed cutting edge, molar tubercle obscure, palp rather .-mall. 

 three-jointed. 



.l/./j-iV/i/vv/.v with small inner and outer plates, palp well developed. 



First gnathopods chelatc in the females, chelatc or suite-Delate in the males. 



Second gnathopod* longer than the first, perfectly chelate. 



Third uropod* uniramous. 



TeLton entire. 



The genus Sehti has been successively allotted to " the confines of the family 

 Lcucothoida (G. 0. Sara)," Stebbing, p. 783 ; the Ly*uma**idte, Delia Valle, p. 773* ; 

 and the Corophidse, Chevreux.f p. 111. As none of these positions is satisfactory, I 

 have thought it better to establish a new family for it. As for the geutis, it appears to 

 me extremely doubtful whether the original species (S. iniiomiiujta, A. Costa, of Sp. 

 Bate, Brit Mus. Cat, p. 159), as described by him, ever existed ; it was repudiated by 

 A. Costa. I propose, therefore, to call it Seba, Stebbing, 1875, with Sef*i naundersi, 

 Stebbing, as the type. 



SEBA ANTARCTICA. (PL 13, fig. 22.) 

 Seba aniaretifa, A. 0. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 151. 



Common in sponges at Hut Point 



The females of this species agree in the smallest detail with the very careful and 

 accurate description of Seba saundtrsi, Stebbing, in the ' Challenger ' Report, and I have 

 very little doubt that it is identical. For reasons given elsewhere,^ however, it is 

 impossible, in the absence of the description of the male from the same locality M 

 S. sounder*! (off Cape Virgins, Patagonia), to be certain of this. 



For the description of the female I refer to that of S. saundersi a(>ove mentioned. 

 The males appear to l>e dimorphic ; the commoner form is only to IN- distinguished 

 by the absence of the incubatory lamella;. In one gathering, however (W.Q., 19 Mar., 

 1902, 10 fm.), two male specimens, measuring respectively 7 mm. and 5 mm., occurred ; 

 the length of females with ova and small males being 4*25 mm. In addition to their 

 larger size, these were remarkable for having the moral joints of the last three pain of 

 peneopods greatly expanded behind, especially in the larger of the two. 



* Fauna and Flora <L Golfa* v. Seapcl. Oammarini, p. 778. 



t Amphipota prorenant Hen CampagiM* <1e I'FTirondelle (1000), p. 111. 



t Ann. and Mag. Nat. Hut. XVII. (10U6), p. 500. 



