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Gen. 1. ^Ega, Leach, 1815.
Generic diameters. Body rather compact, with very hard integuments,
and the segments of mesosome nearly equal in size, the 4 posterior ones
generally having a line running across them dorsally. Coxal plates thick, sculp-
tured outside with 2 curved ridges, and produced posteriorly to an acute point.
Metasome not much narrower than the mesosome, its 5 anterior segments very
short, and having the epimera acutely produced. Eyes large, reniform, sometimes
approaching dorsally, so as to meet in the middle. Superior antennas rather short,
with the first 2 peduncular joints more or less expanded. Anterior lip having in front
a smooth linguiform plate (epistome) projecting between the bases of the inferior
antennae. Posterior lip terminating in 2 comparatively small, lanceolate lappets.
Mandibles having at the base outside a well-developed 3-articulate palp, inner
part of the body greatly produced, and terminating in a sharpened, knife-shaped
cutting edge, molar expansion wanting. Anterior maxilla? with only a single
narrrow masticatory lobe tipped by short spines. Posterior maxilla? broader, sub-
lamellar, terminating in 2 unequal
lobes armed with recurved denticles. Maxilli-
peds rather strong, epignath confluent with the basal part, masticatory lobe rudi-
mentary, terminal part (palp) 5-articulate, incurved, subtortuous, and armed with
strong recurved denticles. Anterior pairs of legs with the propodos simple cylind-
ric, not expanded, dactylus abruptly curved in the middle, and terminating in a
very acute point; the 4 posterior pairs successively increasing in length,
propodal joint short, and the dactylus comparatively small. Uropoda
basal part produced at the inner corner to a narrow lanceolate process.
with the
with the
Remarks. This genus was established as early as in the year 1815 by
Leach, and represents the type of the family ^Ey'idce.
It is chiefly distinguished
from the other 3 genera represented in the Norwegian fauna, by the compara-
tively broad metasome, the large reniform eyes,
the structure of the antenna? and
that of the mandibles and maxillipecls. Moreover, some differences are found in
the structure of the legs. The yEga? comprise some of the largest known Iso-
poda, and are well known by our fisher-men by their frequent occurrence on the
skin of fishes of various kinds. They are generally named here in Norway
'Fisk-Bjorn", that is, fish-bear. The genus comprises rather a large number of
species from different parts of the Oceans, amounting to more than 20 in all.
To the fauna of Norway belong 7 species, to be described below.