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anal segment rounded at the tip. Eyes wanting. Basal expansion of antennulse
very broad, and divided into 21 closely crowded teeth. Antennae with the fla-
gellum scarcely longer than the last 2 joints of the peduncle combined. Uropoda
with the outer ramus about half as long as the inner. Length
about 4*/2 mm., of male 0.65 mm. Parasitic on Idothea baltiea.
Remarks. -As above indicated,
of adult female
the differences between this form and the
other species recorded by MM. Giard and Bonnier, C. Meinerti, are very slight,
and it is, indeed, chieflv the occurrence of both forms that has led the said
f V
authors to regard them as 2 distinct species. It may be that a closer compara-
tive examination of young females specimens, males and larvae, might reveal better
distinguishing characters ; but the adult females, at least, of these 2 forms appear
to me to be nearly undistinguishable from one another.
Occurrence. This form has certainly not yet been recorded from Nor-
way; but, as the species of Isopod, Idothea baltiea Pallas, on which it is found
parasitic, is very common along our whole coast, it is very probable that,
on a
closer investigation, it will in reality be found to exist also off the Norwegian
coast. The figures here given are from Danish specimens kindly sent to me from
the Museum of Copenhagen. In none of these were fully developed embryos
found, and I have therefore not been able to give any figure of the characteristic
1st larval stage. The specimens examined by MM. Giard and Bonnier were
likewise from the Danish coast, and this form has. indeed not yet been found
in other places, unless the Greenland form, C. Meinerti, should prove
same species.
Gen. 5. MunnOniSCUS, Giard & Bonnier, 1895.
Generic Characters. Body of adult female forming
to be the
a thin-skinned sac
of a somewhat irregular bilobed form, without any traces of segmentation, but
exhibiting dorsally a well defined, though rather small opaque area; that of
younger female more regular in form, with the opaque area occupying almost the
whole dorsal face. No distinct affixing apparatus present. Male unknown. Para-
sitic in the incubatory pouch of Isopoda belonging to the family Munnopsidce.
Remarks. This genus was proposed in the year 1895 by MM. Giard and
Bonnier, to include the form previously recorded by the present
author as
Cryptothiria marsupialis and, indeed, with some doubt referred by him to Dana's
genus. We only know at present of a single species, to be described below.