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Gen. 4. ClypeOnlSCUS, Giard & Bonnier. 1895.
Generic Characters. Body of adult female forming
a somewhat flattened
bag of oval form, without any distinct segmentation, but with the lateral parts
slightly lobular, and both extremities briefly incised ; dorsal face convex and exhi-
biting somewhat in front of the middle an opaque area, ventral flattened, with a
longitudinal slit leading to the inner cavity, and admitting of being closed by a
number of small valvular lamellae defining it on each side. Within the bottom of
the posterior incision an extremely small projection occurs, constituting the hind
extremity of the animal. No distinct affixing apparatus present. - - Male comparatively
short and thick, with the basal expansion of the antennulse very broad and
densely pectinate. Coxal plates likewise distinctly pectinate. Antennae comparatively
short. Uropoda
with the outer ramus much smaller than the inner. 1st larval
stage distinguished by the presence of a broad operculiform plate covering the
ventral face of the tail. Parasitic in the marsupial cavity of Isopoda belonging to
the family Idotheidce.
Remarks, This genus, recently established by MM. Giard and Bonnier,
is well distinguished from the other Cryptoniscian genera by the flattened cake-
like shape of the adult female, as also by the peculiar shield-like plate occurring
in the 1st larval stage beneath the tail. It is, indeed, the latter character which
has given rise to the generic name proposed by the said authors. They record
2 different species, the distinctness of which, however, appears to me somewhat
questionable, although they are from widely
on different species.
distant localities and have been found
ClypeoniSGUS Hanseni, Giard and Bonnier.
(PL XCIX, fig. 1).
Clypeonlscus Hanseni, Giard and Bonnier, Contributions a 1'etude des Epicarides, in Bulletin
scientifique de la France, T. XXV, p. 444, PI. VII X.
Specific Characters. Body of adult female oval quadrangular in outline,
with both extremities nearly alike, or the anterior very little narrower than the
posterior, lateral parts divided into 5 6 rounded lobes, which, however, often
appear less regular and sometimes are almost obsolete ; dorsal opaque
area not
very distinctly defined, and oval in form ; caudal prominence very small, clavi-
forrn, briefly bilobe^d at the tip. - Male
oval pyriform in outline, but little more
than 3 times as long as it is broad; cephalic segment evenly curved in front;