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2 middle figures on PI. 96) are of very considerable size, projecting with their
outer, broadly rounded parts far into the marsupial cavities, and they are divided
by several irregular folds, so that they might have presented
themselves for the
above mentioned authors as consisting each of several superposed plates. It is also
very probable that the maxillipeds, owing to their anomalous direction, have been
taken by them for another pair of incubatory plates. The 2 narrow, juxtaposed
folds, which extend behind the oral area, and which, by their posterior lappet,
serve for closing the posterior openings of the marsupial cavities, are described by
MM. Giard and Bonnier as the 5th pair of incubatory plates. It may
they answer to tbe plates so named in Daju*,
be that
but between these folds and the
above described 1st pair no other plates exist, for a slight lobe found at about
the middle of the length of the folds, and extended laterally within the mar-
supial cavities, has on dissection turned out to be only a lateral lappet issuing
from these folds (see the upper middle figure on PI. 96). The appearance of
the immature females, of which I have examined specimens scarcely exceeding
1 mm. in length, is rather perplexing ; for. contrary to what is the case in
Dajus and probably also in Notophryxus, the body exhibits in such specimens a
still more compact form than in fully grown females, and there is scarcely any
trace of a caudal division. In such young specimens, the appertinent male is
generally found to be still in the Cryptoniscian stage, and is invariably found
clinging to a peculiar, more or less contorted fleshy cord hanging down from
the posterior hollowed part of the body answering to the caudal part in fully
grown specimens. The same peculiar mode of affixion could also be proved to
occur in adult specimens, and this cord therefore appears to be an integrant
part of the genital apparatus
of the female. MM. Giard and Bonnier have also
seen a cord of this description in the specimen examined by them ;
but they have inter-
preted its significance in a very different manner, believing it to belong to a parasitic
(
'opepod (Aspidoecia Normani) found by them attached to the same host (a spe-
cies of the genus Erythrops) below the body of the Aspidopliry.rtts, and accord-
ing to their assumption, at the same time affixing itself by
the aid of this cord
to the Epicarid. This supposition is evidently quite wrong. For the above-named
<
'opepod. which I have found not infrequently attached to different places of the body
in specimens of En/thrnjix. has in reality nothing to do with the Aspidophr/jxus,
and the apparent association of the 2 parasites, as observed by MM. Giard and
Bonnier, has certainly
been due to a mere accident,
Occurrence. -I have found this peculiar Epicarid not infrequently along
the whole south and west coasts of Norway, and northwards at least to the Lo-
foten Islands, especially infesting species of the Mysidian genus En/thro^. Its