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simple, conic; posterior antennae with the flagellum 4-articulate ; legs
structure; uropoda
decapodous Crustacea.
of uniform
with the inner ramus shorter than the outer. Parasitic on
Remarks. This family comprises the more differentiated forms of Epica-
rida, in which the retrograde metamorphosis is less pronounced. Yet the adult
female in every case exhibits an appearance very different from that of the male
and the larvae, the body being more or less deformed and asymmetrical, though
its segmentation, as a rule, is distinct at least on the dorsal side,
with the 3
chief divisions well defined. The greater number of forms are found as parasites
in the branchial cavity of higher Crustacea ; but there are a few forms which infest
the ventral or dorsal face of the metasome of their hosts, and which also in several
other respects differ considerably from the others, and might therefore perhaps more
properly be separated into a particular subfamily (the genera Athelges and
Phryxus). Rather a great number of genera have been established, especially
by M.M. Giard and Bonnier; but I believe that some of these genera
are not
very well defined, so that a reduction may perhaps be found to be necessary.
In the following pages will be described 6 genera, at least 5 of which are
stated to belong to the fauna of Norway.
Gen. 1. BOpyrUS, Latr., 1804.
Generic Characters. Body of female broad, flattened, rather asymmetrical,
with the segments of mesosome firmly connected. Cephalon deeply immerged
within the 1 st segment of mesosome, frontal edge broad, lamellar. Lateral parts
of mesosome slightly elevated, subcontiguous, coxal plates inconspicuous. Meta-
some narrowed, with the segments confluent in the middle of the dorsal face,
epimeral plates distinct, subcontiguous, last segment resembling them. An-
terior antennre distinctly 3-articulate, posterior ones apparently consisting of
only 2 articulations. Terminal joint of maxillipeds well defined, broadly
oval or
cordiform. 1st pair of incubatory lamella rather large, divergent, distal segment
terminating in a narrow linguiform lobe; the 4 succeeding pairs widely apart,
leaving a -broad open space in the middle, the marsupial pouch being here closed
by the carapace of the host. Legs very small, concealed within the lateral edges
of the mesosome. Pleopoda simple, lamellar. Uropoda wanting. Male with the
segments of metasome imperfectly defined. Parasitic in the branchial cavity of
prawns.