download pdf

225
contained in the marsupial cavities is rather considerable in fully grown females,
though not nearly so immense as in the Bopyridse. They show with great di-
stinctness through the thin body-walls bounding
these cavities.
Distribution. Greenland (Kr0yer), Labrador (Packard), Sabine Island
(Buchholz), Spitsberg (Hoek), Jan Mayn (Norw. North Atl. Exped.), the Murman
coast (Stuxberg), the Kara Sea (Hansen).
Gen. 2. NOtOphryXUS, G. 0. Sars, 1882.
Generic Characters. Body of adult female ovate, more or less depressed,
and but slightly curved, with the cephalic part projecting in front, and the lateral
parts greatly swollen, though scarcely expanded anteriorly. Metasome forming
a semicircular, incurved plate, without any appendages. Marsupial rooms sub-
contiguous in the middle of the ventral faces. Antennse lamellar, imperfectly
articulated. Oral area rather small, contracted behind. Tips of mandibles pro-
jecting from the oral cone in the shape of 2 narrow plates
armed with recurved
teeth. Maxillipeds folded hackwards over the very large and broad sternal plate.
Only a single pair of incubatory plates present, issuing from the base of the anterior
pair of legs, and divided into 3 diverging lappets. Legs small, of normal structure.
Adult male resembling that of Dajus. Larvae in the 1st stage distinguished by the
large size and peculiar structure of the uropoda. Parasitic on Mysidse and
Euphausiidse, being, as a rule,
attached to the dorsal face of their hosts.
Remarks. Though in the general appearance of both sexes this genus
is rather like the genus Dajus, it is found, on a closer examination,
to differ in
several respects very pronouncedly. Thus, the antenna, at least in the type
species, exhibit a rather anomalous appearance, forming broad, inarticulate
plates, which together constitute a broad lamella bounding
front. Moreover, the maxillipeds, instead of being turned anteriorly,
the oral area in
are folded
hackwards over the large sternal plate, looking at first sight merely like a pair of
incubatory plates. Of the latter there is only a single pair present, issuing from
the base of the 1st pair of legs, and exhibiting a very irregular form. Finally,
there is no trace of any appendages on the metasome. Four different species
have been recorded by the present author as belonging to this genus ; but, as
remarked by MM. Giard and Bonnier, it is very probable
29. Crustacea.
that some of these