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of the inner. Colour whitish, semi-pellucid. Length of adult female 4 mm., of
male 3 mm.
Remarks. The present form was first described by the present author
as Desmosoma tenuimanum, and at the same time the anomalous characters of
this species were pointed out. The Eugerda globiceps of Meinert is unquestionably
the same species, and accordingly only the generic name proposed by that author
ought to be retained. In outward appearance, it bears a great resemblance to
Desmosoma lineare, but may, on a closer examination, be easily distinguished by
the more elongated inferior antennae, the extremely slender 1st pair of legs, and
the distinctly biramous uropoda.
Occurrence. This species was first detected at Langesund, south coast of
Norway, and I have subsequently found it, though rather sparingly,
in the inner
part of the Christiania Fjord, at Drobak, as also in the Trondhjem Fjord.
Distribution. Skagerak and Kattegat (Meinert).
Gen. 6. EchinOpleura, G. 0. Sars, n.
Sj'n: Desmosoma, G. O. Savs (part).
Generic Characters. Body slender, attenuated, and abruptly
narrowed in
the middle, 4th and 5th segments of mesosome forming together, as in the genus
Ischnosoma, an hour-glass-shaped section. Caudal segment deeply constricted at
the base. Lateral parts of all the segments coarsely denticulated. Antennae of a
similar structure to that in the 2 preceding genera. Mandibles without palps,
cutting edge in the right mandible simple, in the left very slightly bifid, molar
expansion extremely small, dentiform, tipped by a single bristle. 1st pair of legs
but slightly differing from the 3 succeeding ones, all 4 pairs rather slender, and
edged with scattered spiniform bristles; the 3 posterior pairs still more slender,
imperfectly natatory, though approaching in structure those in the 2 preceding
genera. Uropoda simple, Inarticulate, distal joint the larger.
Remarks. The present new genus is established, to include the rather
anomalous form previously described by the present author as Desmosoma acti-
leatum. On a closer anatomical examination of this form,
I have found it to
differ in some points so materially from the 2 other species of Desmosoma, that
it should more properly be regarded as the type of a separate genus,
in some
respects exhibiting some resemblance to the genus Ischnosoma. The structure of
17 Crustacea.