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206
able want of correctness, as regards the said author, had not been universally known.
\Ve also see, that M.M. Giard '& Bonnier, who may be presumed
to have ex-
amined the species of Hesse, do not doubt that Pltri/.nis longibranchiatus of Sp.
Bate & Westw., one of the species here described, is congeneric
with Pleuro-
ci-f/jtta yi.tlathece Hesse; they even regard this form as merely the young female
(,,phryxoid stage") of Hesse's species, an opinion which I, however, am not
prepared to endorse. Three different species of this genus have hitherto been
stated to belong to the fauna of Norway, and they will be described and figured
in this work.
1. Pleuroerypta longibranehiata, (Sp. Bate & Westw.).
(PI. LXXXVI. tig. a).
Phri/xus longibranchiatus, Sp. Bate & Westwood. Brit, sessile-eyed Crust.
Vol. II, p. 246.
Specific Characters. Body of female but slightly asymmetrical, oblong
pyriform in outline, being gradually narrowed behind. Cephalon
of moderate
size, frontal edge strongly curved, lateral corners somewhat produced. Segments
of mesosome well defined, with the lateral parts slightly elevated, coxal plates
forming a somewhat discontiguous border flanking the sides. Epimeral plates of
metasome narrow lanceolate, discontiguous. Eyes small, but distinct. Antennae
shorthand thick, subequal in size. Terminal joint of maxillipeds conical in form,
setous on both edges.", 1st pair of incubatory plates with the distal segment
deeply emarginate ^outside; the succeeding pairs large, overlapping
each other
in the middle. Legs~sruall, scarcely projecting laterally. Pleopoda rather fully
developed and projecting far beyond the epimeral plates, lamelhe narrow lanceo-
late and very distinctly tuberculated. Uropoda of about the same length
as the
lamellae of^the^ pleopoda, but much narrower. Male somewhat depressed, with
the mesosome^ of nearly uniform width throughout, metasome forming
an un-
divided piece, rather broad at the base and gradually tapering to an obtuse
point. Colour not yet stated. Length of female 8 mm.,
of male 2 mm.
Kern uric*. I cannot doubt that the above-described form is identical
with that described in Brit- sessile-eyed Crust, as Phryxus longibranchiatus. The
general form of the body is the same, and the structure of the pleopoda seems
also to agree perfectly, well. The statement of the British authors that the last
segment of the metasome carries 4, instead of 2 appendages, is certainly
due to
a miscomprehension, and may easily be explained by the close resemblance of