40 
R. NORRIS WOLFENDEN. 
rostrum directed forwards, with slight curve downwards, the rostral spines not at all 
divergent, as in Sars’ picture of BEtidiopsis. The whole cephalothorax is studded with 
fine and closely-set prickles. Abdomen of four segments, slender, the genital only a 
little larger than the next, with strong ventral protuberance, > Ah 2 > Ah 3 > Ah 4. 
Furcal segments as long as the anal, and twice as long as broad. Tail bristles four on 
each side, with very short and delicate ventrally placed accessory bristles. Anterior 
antennae reaching just beyond the end of the genital segment, the first two joints 
comparatively large and as long as the next five joints, the combined eighth and ninth 
joint as long as the two joints either proximal or distal to it, the eighteenth and nine¬ 
teenth joints longer than those proximal or distal, and the twenty-fourth separate from 
the twenty-fifth. All joints only sparingly setiferous. 
Posterior antennae with exopodite a little longer only than the endopodite. 
Anterior foot-jaws with the outer margin of the basal only a little convex, the 
fifth lobe longer than the four proximal and nearly equally-sized lobes, the Ri small 
but distinctly segmented. Each lobe with three bristles, two each on the first, second, 
third, and one on the fourth, being stout, long, and with wide apart stiff marginal 
bristles. Bristles of Ri long, not feathered, but slightly serrated marginally. 
Posterior foot jaws having proportionately B 1 : B 2 : Ri = 10 : 12 : 5. B 2 
therefore a little longer than B 1, and over twice as long as Ri ; B 1 two and a half 
times as long as broad, with two small lobes with respectively two and three short 
bristles ; B 2 four times as long as broad, its marginal bristles very small and distal of 
the middle. Ri short and distinctly five-segmented. 
Maxillae, Le 1 with nine bristles and its outer margin nearly straight; B 2 with 
five, and not segmented from Ri with thirteen bristles; Le 2 a small lobe, but without 
bristles ; Re small, longer than broad, and with ten bristles ; Li 1 with nine large hooks 
and four bristles ; Li 2 and 3 well-formed lobes. 
First feet. Ri one-jointed ; Re three-jointed, with three long thin marginal 
spines. 
Second feet. Ri two-jointed, Ri 1 short, Ri 2 very elongated, and nearly four 
times as long as Ri 1. The whole Ri only extends to the distal end of Re 2. On the 
distal part of the surface of Ri 2 is a bunch of fine hairs ; Re 3 is as long as Re 1 + 2, 
and its end saw is longer than the Re 3 and beset with a great number (exceeding 
fifty) of closely-set teeth, of which those in the middle are the largest. 
Fourth feet. Ri and Re of three segments each. Ri proportionately longer than 
in the other feet, and the third segment as long as Ri 1 + 2, and a little over three 
times as long as broad, with fine hairs on the surface distally. Re 3 much longer than 
Re 1 + 2 and over three times as long as broad. Its end saw three-quarters as long 
as the Re 3, and with over fifty closely-set teeth. No fifth feet. 
The chief points in which this Antarctic species differs from that of the northern 
seas are in its greater size, the greater strength of the rostrum, the rather different 
body proportions, and the more equal size of the rami of the posterior antennae. The 
