288 DISCOVERY REPORTS 



in two short spines placed some distance in front of the bases of the uropoda. A trans- 

 verse curved ridge, which is prolonged backwards into three short spines, the median 

 one the larger, extends across the segment in a line with the terminal spines of the lateral 

 keels. 



Remarks. Beddard ( 1 884 Z), p. 43) states that the antennules and antennae are of equal 

 length and that " the antennae of the males possess a series of delicate lamellar processes 

 (pi. ii, fig. 6) arranged in a single line along the inner side of most joints, being absent 

 only from a few of the extreme distal and proximal joints". He also says that "the 

 anterior margin of the middle joints has a series of short curved spines like those already 

 -described for S. porodoxa". I find on examination that the antenna of this species is 

 considerably longer than the antennule, the latter only extending to the end of the 

 peduncle of the former. I also find that there is only one set of spines on the flagellar 

 joints of the antennae, and that these correspond with the " deHcate lamellar processes " 

 of Beddard's description. The spines are also present in the female, so that they can no 

 longer be regarded as a secondary sexual character. These lamellar processes, which are 

 present on the ventral surface of the joints, presumably correspond with the "short 

 curved spines" of S. paradoxa; similar though somewhat smaller processes occur in 

 S. polaris. 



The maxillae are of the usual type, except that the inner articulating lobe is slightly 

 broader than that of most species and bears seven pectinate setae instead of the more 

 usual numbers of either two or four : the fixed lobe bears fourteen or fifteen of these 

 setae. 



The maxiUipeds (Figs. 2 b, c) agree with Beddard's description except that the "small 

 protuberance carrying three stoutish hairs", which he states (1884 />, p. 43) to occur 

 on the summit of the terminal joint of the palp, appears to be an extra, very minute 

 joint which articulates with the so-called terminal joint at its outer distal angle. This 

 small joint which occurs in other species of the genus probably represents the vestigial 

 fourth joint of the five-jointed palp of the ancestral type. 



The thoracic appendages have been described already, but the form of the dactylus 

 of the third appendage of the female and of the immature male, and of the fourth of the 

 adult male appears to have been overlooked. The dactylus of these appendages (Fig. 40) 

 is somewhat flattened, and bears, on the anterior edge of the distal third of its length, a 

 series of curved though flattened spines which increase in size towards the extremity. 

 Arising between the two most distal of the spines is a strong seta which is densely 

 plumose, and three setae, the middle one of which is sparsely plumose, spring from a 

 slight depression on the posterior margin. The dactylus of the other appendages is less 

 flattened and never bears this row of spines, but a plumose seta (often broken), a couple 

 of strong spines and a few setae may be present at its distal extremity. The dactylus of 

 the seventh appendage in the male is shorter than in the female, recurved, bearing a 

 number of hairs on its outer margin, whilst the propodus and carpus bear groups of 

 strong setae on their inner margins. 



The endopod of the fourth pleopod is bifid, with the inner branch prolonged for some 



