WALKER—AMPHIPODA GAMMARIDEA. 329 
the 5th, which is rather longer than the 6th and finely setose on the hind margin; 6th 
joint (hand) tapering to the base of the dactylus, sparsely setose. Dactylus bifid, with 
a comb-like process at the base. 
Pereeopod 8. Second joint narrowing downwards, the lower two-thirds of the hind margin 
deeply serrate, with setules between the teeth; 3rd and 4th joints short, 4th wide. 
Per. 4. Hind margin of 2nd joint concave below the middle, produced downwards, 
moderately serrate ; 4th joint narrower than in per. 8. 
Per. 5. Hind margin somewhat convex, produced downwards, slightly serrate ; 4th 
joint narrower than in per. 4. 
Uropod 1 reaching the end of uropod 3, peduncle longer than rami, outer ramus 
slightly the longer. 
Ur. 2 not reaching the end of ur. 3, structure as in J. taurus. 
Ur. 3. Peduncle subequal to rami, stout, with 4 spines on the distal half of the upper 
margin ; inner ramus rather shorter than outer (fig.), the 2nd joint almost as long as 
the Ist, with a curved spine at its base. 
Telson cleft three-fourths of its length; ends of the divisions truncate with rounded 
angles without distal spine or notch (fig ). 
Length of male 8-9 mm. 
This species may be easily recognized by the deeply serrate hind margin of perzeopods 
3 and the structure of the telson; in other respects it resembles J. tawrus, Costa, as 
figured by Della Valle. 
Genus STEGOCEPHALUS, Boeck. 
6. Stegocephalus globosus, sp.n. (Plate 42. fig. 2.) 
I. Farquhar: Plankton, s, 250-750 fms.: two. Desroches: Plankton, k&, 250 fms. : 
several, 
Rostrum small. Mesosome very tumid, the first 4 side-plates fully twice as deep as 
the segments, with sharp lower angles, concealing all the legs except per. 5: the 1st is 
triangular; 2nd and 3rd narrow above and widening below; 4th subequal in width to 
the preceding 3 united ; the margins fit accurately together and, the segments being 
bent inwards below, form a complete protection to all but the last pair of perzeopods. 
The lower outline forms almost a perfect semicircle. 
The hind epimeral angle of pleon segment 3 is bluntly quadrate. 
Eyes obscure. 
Ant. 1 considerably shorter than ant. 2; peduncle subequal to the Ist joint of the 
flagellum ; this is 7-jointed, the 1st joint longer than the next 2 unitcd, the last 8 joints 
long and slender. Accessory flagellum one-fourth as long as the Ist joint of the 
flagellum, 1-jointed, with a long terminal seta. 
Ant. 2 slender, Ist and 8rd joints subequal, 2nd shorter; flagellum 13-jointed, sub- 
equal to the peduncle. 
Mandibles: both cutting-edges of the left denticulate (fig. 2, M.). 
Gnathopod 1. Second joint subequal to the rest of the limb; wrist longer and wider 
SECOND SERiES.—ZOOLOGY, VOL. XII. ME 
