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ever, rather different, and very strongly built, prehensile, carpus considerably ex-
panded, and armed inside with 2 long spines, propodos oblong oval, with a strong
spine inside, dactylus strong and curved. Female operculum with a spiniform
projection near the base; that in male simple,
not transformed as in other
Asellota. Genital prominence in male very large, spiniform, recurved, issuing
from the ventral face of last segment of mesosome, immediately in front of the
operculum. Uropoda in both sexes of the same appearance, projecting but slightly
beyond the edge of the caudal segment, outer ramus considerably
the inner, Colour whitish, semipellucid. Length
male iy2 mm.
smaller than
of adult female 2 mm., of
Remnrl-x. This form was first described by the present author only from
female specimens. The male, of which 2 specimens were found subsequently
among the females, looks so very different,
that at first I was in some doubt of
its belonging to the same species. After having examined more closely the several
appendages, I cannot, however, doubt that it is in reality the male of the present
species. The 1st pair of legs are certainly very different; but this may be merely
a sexual character; for in all the other appendages,
the resemblance to the female
is very close. It is a very remarkable fact, that the operculum in neither of the
2 specimens examined showed any trace of the usual transformation, though the
male character of the specimens otherwise could easily be demonstrated, both by
the greatly projecting sexual prominence, and by the presence of well-developed
testes shining distinctly through the integuments in their usual place. In the
Caspian species, on the other hand (of which as yet only a solitary male specimen
is known), the sexual characters were quite normally displayed.
Occurrence. I have as yet only found this form off the Lofoten Islands,
at Skraaven, in depths ranging from 120 to 250 fathoms. Out of Norway, it
has not yet been recorded.
Gen. 2. MacrOStyllS, G. O. Sars, 1863.
Syn : Vana, Meinert.
Generic Characters. Body narrow, sublinear, with the 3 posterior seg-
ments of mesosome very sharply marked off from each other,
the 4 anterior more
densely crowded together. Cephalon rather large, subtriangular, frontal part con-
siderably produced. Caudal segment oblong, obtusely produced at the tip. Supe-
rior antennae extremely small, with the ilagellum rudimentary. Inferior antennae