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larval skin, and deeply immerged within the body of the host, being anchored by
a pair of long, flexuous, root-like processes.
- Adult male exactly resembling the
female larva of last stage, being rather slender, and without eyes ; hind expansion
of basal joint of antennulse divided into a restricted number of teeth, coxal
plates coarsely pectinate; outer ramus of uropoda much smaller than the inner.
Parasitic on Ostracoda.
Remarks. This genus was established in the year 1884 by Dr. Kossman,
to include the peculiar parasite briefly described and figured by the present
author in his ,,0versigt" as Cryptothiria cypridince. I now fully admit that this
form ought to be regarded as the type of a distinct genus, but cannot,
on the
other hand, agree with MM. Giard and Bonnier, that the parasitism of this form
on an Ostracod should make it necessary to place it even in a separate family.
The structure of the male arid the last larval stage of the female do not exhibit
any essential differences from those found in other Cryptoniscidce. The genus
comprises as yet only a single species,
Cyproniscus cypridinse,
to be described below.
(PI. XCVII, PI. XCVIII, fig. 1).
G. 0. Sars.
Cryptothiria cypridince, G. 0. Sars. Oversigt af Norges Crustaceer I, p. IB, PL 2, fios. 17 21.
Specific Characters. Body of adult female almost semi-globular in
shape, with the dorsal face greatly vaulted, the ventral one concave, anterior
extremity, turning forward in relation to the host, subcordiform. posterior nar-
rower and inflexed, obtuse at the tip. Dorsal part of body well defined from
the lateral parts, and divided by distinct transversal lines into 7 segments, each
forming an obtuse gibbosity; lateral parts moderately expanded and unsegmented.
Integuments very thin and pellucid, without any obvious opaque area dorsally.
Immature female somewhat varying in form, more generally clavate, with the
dorsal margin more or less deeply indented between the segments, posterior
extremity narrowly exserted and deflexed, lateral parts not defined from the
dorsal.
-
Still younger female, immediately after the transformation, fusiform,
but slightly curved with the ventral face very convex in front, neck constricted
and still covered by some of the anterior segments of the larval skin, cephalic
part wholly immerged within the skin of the host and exhibiting
strongly denticulated recurved projection, root-like filaments long
in front a
and flexuous.
Male (and female in last larval stage) long and slender, sublinear, with the
dorsal face finely striolate transversally. Cephalic segment evenly rounded in front;
30. Crustacea.