CRUSTACEA FROM THE FALKLAND ISLANDS. 363 
pereeon segments are extended laterally outwards over the side- 
plates. The latter agree with those figured by Walker and 
Chevreux for B. walkeri. The subacute “medio-dorsal extension 
of the last pereeon segment and the first two pleon segments is 
very pronounced, as is that of the third pleon segment, but this 
last is distinguished from the others by its obtuseness. The 
second and thir d pleon segments have the postero-lateral angles 
minutely acute. The telson has an extremely short division 
between the subacute apical lobes, which reach a little beyond 
the peduncle of the third uropod. In both specimens examined 
the lobes were slightly unsymmetrical. 
The eyes are round, not crescentic as in B. giganteus, nor large 
and reniform as in B. walkeri. The first antenne agree with the 
former only, in having no accessory flagellum; the principal 
flagellum showed short filaments on the first, second, fourth, and 
seventh articulations, and so on at each successive third to the 
twenty-second or twenty-eighth, the total in one specimen being 
30, in another 33. The longer second antennz show a flagellum 
of 46 joints, the proximal group very short, those towards the 
end rather long, the whole flagellum longer by half than that of 
the first pair. Hach mandible has an accessory plate, that on the 
left forming five little teeth, that on the right having only two, 
which are longer and apical instead of serial; the third joint 
of the palp is shorter than the second. The lower lip appears 
to be without inner lobes. The first maxille have four plumose 
sete on the apical margin of the rather broad inner plate 
second joint of the palp long. 
The first and second gnathopods are extremely similar in the 
female, the hand oval, narrowest at the finger-hinge, the palm 
making a continuous curve with the hind margin, its limit 
defined by spines which the tip of the curved finger reaches ; 
hand and finger slightly larger in the first gnathopod than in the 
second. The fifth perseopod has the hind margin of the second 
joint sinuous, the greatest width of the joint being near its base. 
The first ur opods have a peduncle much longer “than the inner 
ramus, which is longer than the outer, bis shorter than the 
inner ramus of the second pair, that ramus exceeding its peduncle 
in length. The third uropods have the rami subequal, much 
longer than their peduncle and somewhat longer than the 
telson. 
Length of one specimen 12 mm., that of the specimen figured 
9 mm. in its bent posture, probably about 12 mm. if extended ; 
it contained numerous eggs. 
Locality. Low spring tide at Roy Cove, the specific name 
alluding to that of the place so diligently examined by Mr. Val- 
lentin. 
Gen. PontoGENEIA Boeck. 
1871. Pontogeneia Boeck, Forh. Selsk. Christian. 1870, p. 193. 
1906. 5 Stebbing, Das Tierreich, vol. xxi. p. B59, 
