download pdf

229
transversal folds as an indication of segments, ventral face concave, or more
properly grooved along the middle. Cephalic parts narrowly truncated in front,
and defined laterally from the wing-like projecting lateral parts of mesosome by
deep incisions, its ventral portion forming a narrow quadrangular plate deeply
emarginated behind. Oral area very small, rounded, placed
far in front.
Body of immature female nearly quadrangular in outline, scarcely tapering
posteriorly, hind extremity bluntly truncated, cephalic part narrowly produced.
at all
Adult male narrow, linear, somewhat resembling that of Notuphri/xtix ovoides,
but having the metasome considerably more produced, tapering distally, and di-
vided into 5 not very sharply defined segments, the last of which carries 2 in-
distinctly bifid appendages (the uropoda). Young male, still in the cryptoniscian
stage, resembling that of Dajus, though having
the front narrower and the oral
sucking disc of smaller size. Colour of female somewhat varying
in different
specimens, the dorsal face being more or less variegated by a dark brownish
red pigment, generally arranged in broad transversal bands. Length^of female
attaining 3 mm.,
of male 0.70 mm.
Remaflcs. As above mentioned, this is, in my opinion, the only as yet
known species of the genus. As regards the supposed new 7
species described by
MM. Giard and Bonnier, and kindly dedicated to the present author, the only
distinguishing character given is the smaller number and comparatively greater
size of the ova contained in the marsupial cavities ; but this is simply due to the
circumstance that the specimen examined was of rather small size, in which case
the ova cannot of course be so numerous as in larger specimens, and must
also naturally appear of greater size in relation to the parent animal.
The other apparent differences, relating to the structure of the _ antennae, oral
parts, and incubatory plates, evidently are due to an imperfect examination. It
is, indeed, very difficult to get any correct idea of these parts without a very
careful dissection and preparation, and such a close examination could not, as
above stated, be instituted by the said authors. As to the incubatory plates, MM.
Giard and Bonnier say that they have found them to be of essentially the
same structure as in Dajus mysidis. and they are also thus represented in
one of the detail-figures given. The fact is, however, that in the present genus
these plates, both as to form and number, are very
different from those in
Dajus, and much more resembling those in Notophryxus. As in that genus, only
a single pair of such plates are developed in front, to close^the anterior open-
ing leading to the marsupial cavities, and these plates in this case too,
issue from the bases of the foremost pair of legs, the next succeeding legs
having no traces of plates at their bases. The above-named plates (see the