252 CRUSTACEA. 



5-10, and Hombron and Jacquenot, Voy. au Pole Sud., Plate 4, figs. 

 3-7. In our specimen, the length of the carapax was 4-1 lines; great- 

 est breadth, 5'75 lines; ratio of length to breadth, 1 :1-41. Colour 

 of carapax, brown, or brownish yellow clouded with brown. The front 

 is slightly convex, and has a length a little exceeding the breadth of 

 the buccal area ; it is imperfectly six-lobed, the two inner lobes nar- 

 rowest, and all spinulous, with the spiniform teeth largest near the 

 orbits, and a little incurved. Antero-lateral margin with four or five 

 small spiniform teeth, and a few additional spines on the surface ad- 

 joining. Surface of carapax without distinct areas, slightly pubescent, 

 somewhat shining. The orbits closed as in Ruppellia. Outer an- 

 tennae short. Inner antennae in transverse fossae. Outer maxillipeds 

 with inner margins in close contact, third joint very short, and having 

 a transverse row of spinules; in an under view, the maxillipeds are 

 thrown so far forward as to conceal the inner antennae. Inner and 

 outer surface of hand smooth and shining, upper margin broad and 

 finely spinous; carpus spinous. Eight posterior legs hirsute above. 

 Abdomen of female broad elliptical, covering the whole space between 

 the basal joints of the legs. 



GENUS TRAPEZIA, Latreitte. 



The genus Trapezia, as accepted by authors, includes two genera, 

 one of which is here named Tetralia. In both genera, the carapax is 

 subquadrate, smooth and shining, with the sides converging posteriorly 

 from near the middle, the front horizontal and broad ; the eyes occupy 

 the angles, and the outer antennae are excluded from the orbit. The 

 true Trapeziae have the following distinctive characters : 



Outer maxillipeds widely separate anterior to middle of second 

 joint, and posterior margin of second joint nearly or quite transverse. 

 Front margin of buccal area (see Plate 15) with an emargination, 

 which terminates the efferent canal. Abdomen of male five to seven- 

 jointed. Anterior legs with the arm much projecting beyond the 

 body, and acute or nearly so at inner apex ; the hand not strongly bent 

 downward at its extremity. Tarsus not unguiculate, truncate at 

 apex and spinulous. Pterygostomian region marked with a line run- 

 ning laterally and backward from near the posterior part of the outer 

 maxillipeds. 



