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tin- body appears less depressed than in most other Isopods. and, as the very much
elongated legs in alcoholic specimens are generally stretched downwards, the body,
unlike that of other Isopods, presents itself to the observer, as a rule, in u
lateral position. We know of 9 or 10 species of the genus, 5 of which belong
to the fauna of Norway, and will be described below.
l. Munna Boecki, Kroyer.
(PL XLIV.)
Munna Boeckii, Ki-oyer, Nat. Tidsskr. Bd. II, p. 612, PI. VI, figs. 19.
Specific Character*. Body of female very short and thick, with the an-
terior division, seen from above, almost circular in outline; last segment of meso-
sonie very small. Caudal segment about half the length
of the anterior division
of the body, ob-pyriform, lateral edges somewhat bulging in their anterior part,
and each armed with 4 short denticles, tip obtusely produced, and exhibiting
ventrally, on each side of the anal orifice, a coarsely serrated lamella. Eyes
rather large, semiglobose. Superior antenna- scarcely reaching to the middle of
the penultimate peduncular joint of the inferior ones, iiagellum composed of 6
articulations, the apical one being extremely small. Inferior antennae moderately
strong, about twice the length of the body, flagellum somewhat longer than the
peduncle. Legs rather strongly built, and rapidly increasing in length posteriorly;
1st pair with the carpus gradually widening distally, and armed inside with a
double row of slender spines, propodos oval inform. Last pair of legs exceeding
the body in length, carpal joint about the length of the 3 preceding joints com-
bined, and rather strong, widening distally, propodal joint long and slender, linear.
Uropoda very small, with the tip transversely truncated. Colour yellowish, very
slightly clouded with darker shadows. Length of adult female 4 mm.
Remarks. This is the species first recorded, and ought accordingly to be
regarded as the type of the genus. It may be easily recognized from the other
species by the very broad, nearly circular fore-part of the body,
the form and
armature of the caudal segment, the comparatively large eyes, and the long, but
rather strongly built legs.
Occurrence. I have met with this form occasionally in a few localities
on the west coast of Norway, in depths ranging from 20 to 50 fathoms, on a
rocky bottom, overgrown with Hydroida and Polyzoa. Kroyer observed the species
at Trondhjem.
Kattegat (Meinert).