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Remarks. This form was described as early as in the year 1767 by
Linnaeus as Oniscus oceanicus, and has subsequently been recorded by Leach and
Bosc under different specific names. It is the largest of our indigenous Oniscoida,
and is moreover easily recognizable by the strongly built antennae and the struc-
ture of the uropoda.
Occurrence. Along the western coast of Norway
this form occurs rather
plentifully, and extends northwards at least to the Trondhjem Fjord. In the
inner part of the Christiania Fjord, on the other hand, I have never met with
it, and it would seem therefore that it deserves its specific name, being appar-
ently restricted to those coasts that are open to the oceans. It is always found
close to the shore, just above high-water-mark, beneath decaying algae and stones,
feeding, it would seem, both on animal and vegetable matter. When alarmed, it
runs away with great agility, to conceal itself in the crevices of the rocks, and
beneath stones.
Faro Islands.
Distribution. Coasts of Denmark, Prussia, Belgium, France, Spain, Britain,
Gen. 2. Ligldlum, Brandt, 1833.
Syn: Zia, Kocli.
Generic Characters. Body oblong, rather convex,
attenuated behind. Ce-
phalon evenly rounded in front. Lateral parts of mesosome less prominent than
in Liyia-j and not defined from the corresponding segments by any distinct groove.
Metasorne comparatively small and abruptly contracted, with the last segment of
inconsiderable size and without jiny epimeral plates. Eyes large and convex.
Antennulse less rudimentary than in Ligia, and distinctly projecting in front.
Antenna less strongly built than in that genus, though of a very similar struc-
ture. Mandibles with a restricted number of penicils, and without any ciliated
lappet behind the cutting part. Maxillipeds more slender than in Ligia, with
the terminal part less expanded, epignath narrow linguiform. Legs very slender,
and greatly increasing in length posteriorly. Opercular plates of pleopoda very
thin, without any obvious branchial structure. Uropoda not very large, basal part pro-
duced at the end inside to a conical process carrying the inner ramus, the latter,
as a rule, smaller than the outer, and provided with 2 long and slender apical
bristles.