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Fam. 2. laniridae.
Characters. General habitus that of the Asettidw, but the lateral parts of
the cephalon always lamellarly expanded. Eyes, when present, suhdorsal. Superior
antenme sometimes well developed, with the flagellum multiarticulate, sometimes very
small, with rudimentary flagellum. Inferior antenna 1
always longer
than the su-
perior, with the peduncle 6-articulate, and generally carrying a small accessory
appendage (scale) outside the 3rd joint. Oral parts normal. Legs subequal in
length, with the dactylus generally hi- or tri-unguiculate ;
1st pair sometimes differing
from the others in being prehensile. 1st pair of uropoda in female transformed
into a single, large, opercular plate, in male constituting the median piece of the
compound operculum, the lateral pieces of which are formed by the copulative
appendages. The 3 succeeding pairs very delicate, the last pair forming simple
smooth lamella?, the 2 preceding ones with the outer ramus narrow and confluent
with the basal part. Uropoda biramous, more or less developed.
Remarks. The forms belonging to this family resemble the Asellidce very
much, as regards their external appearance,
and have also hitherto been combined
with them. Yet the very different structure of the pleopoda makes it, in my
opinion, necessary to place them in a separate family. As additional distinguishing
characters may be mentioned the laterally-expanded cephalon, the subdorsal
situation of the eyes, the distinctly 6-articulate peduncle of the inferior antenna 3
on which, in the greater number of the forms, a small outer appendage, apparently
answering to the scale in higher Crustacea, may be distinguished; finally, the
more uniform length of the legs, the dactylar joint of which moreover,
as a rule,
is hi- or tri-unguiculate. All the known forms are exclusively marine, and, as it
were, replace the Asell'ulce in the Oceans. Several genera have been established,
amounting to 9 or 10 in all, 4 of which only are represented
of Norway.
Gen. 1. lanira, Leach, 1813.
Syn: (hilsroda, Ln.tr.
Hmopomus, Kroyer.
Asellodes, Stimpson.
in the fauna
Generic Characters. Bo Aj oblong, depressed, with the lateral parts of
the segments but slightly produced. (Vphalon large, transversely oval, obtuse in
front, or with a comparatively small rostral projection. Caudal segment rounded.
,