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formation) almost perfectly symmetrical, vermiform. Adult male with the segments
of metasome more or less fused together. Parasitic on the ventral face of differ-
ent Carida.
Remarks. This genus was etablished in the year 1843 by H. Rathke,
to include a peculiar Bopyrid found by him on a species of Spirontocaris (Hip-
polyte), and named Phryxu* ltij>j>olytes. He, moreover, refers to this genus an-
other Bopyrid, P. Paguri, which, however, is now recognized as generically differ-
ent and referable to the genus Atht'/i//^ of Hesse. MM. Giard and Bonnier
transfer the generic name Phry.rus, proposed by Rathke, to a generically differ-
ent exotic Bopyrid, substituting for the northern form a new name, viz.
Heui'iiu-thrus. This however, cannot, be sanctioned, since such a proceed-
ing is quite contrary to the general rule in Zoology. Tf the name Phri/.nis is
to be retained in the present group, it ought certainly to be used for the form,
to which it was originally assigned, and cannot be replaced by a new generic
name, unless the former name is altogether to be abandoned. It may
be that
this will be found necessary, as the name Phryxus is said to be already appro-
priated in Zoology.
The present genus exhibits, it is true, some points of agreement with
the genus Athclgrs, especially as regards the structure of the metasome, but in
several other respects it differs rather markedly, so that it ought evidently to be
kept apart, though forming with it a distinct sub-division of the family Bopyri(hv.
In addition to the northern species described below, MM. Giard and Bonnier
have recorded 4 other species from the Mediterranean; but no description or
figures of these have as yet been given, and their validity is accordingly still
rather problematic.
Phryxus abdominalis, (Kroyer).
(PL XC, XCI).
Bnpijrufi abdominalis, Kvoyer, Nat. Tidsskr, Vol. III. p. 102, PI. I, II.
Syn.: Phryxus hippolytes, Ratbke
Hemiarthrus abdominalis, Giard and Bonnier.
Specific Characters. Body of fully grown female forming an irregular,
globular mass, somewhat varying in form, according to the degree
of distortion
of the marsupial pouch, one of the sides, sometimes the left, sometimes the right,
being much more swollen than the other, and the axis of the body accordingly
more or less twisted to one side or the other. Cephalon comparatively small,