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rather large, sub-discontiguous, 1st pair securiform in shape, posterior corners of
this and the succeeding pairs acuminate. Metasome scarcely occupying y4 of the
length of the body, epimeral plates of 3rd to 5th segments prominent, recurved;
last segment nearly as long as it is broad at the base, outer part conically pro-
duced and plane above. Antennae slender, though scarcely attaining half the
length of the body, flagellum shorter than the last peduncular joint, and having
its proximal articulation scarcely more than half as long as the distal one. Legs
about as in P. Rathkei. Opercular plates of all pleopoda provided
cavities. Uropoda of moderate size, resembling
with air-
those in P. Rathkei. Colour of
dorsal face more or less dark grey, with a regular row of whitish patches on
each side, at the base of the side-plates of mesosome, and an assemblage of less
distinct wavy stripes on each side of the median line; edges of the side-plates
tinged with light yellow. Length of adult male 11 mm.
Remarks. For the identification of this interesting species, not yet found
in any of the Scandinavian countries, I am indebted to Mr. Budde-Lund, who
kindly sent me for comparison some specimens of this form from the central
part of Europe. It is nearest allied to P. Rathkei, but easily distinguishable from
it by the very prominent cephalic lobes, of which the middle one (frontal lobe)
especially exhibits a rather peculiar appearance from its regular
semicircular form.
Occurrence. I have hitherto only succeeded in finding 2 specimens of
this form, a female and a male. They were taken this summer in the neigh-
bourhood of Christiania (Bygd0) beneath loose bark, and were at first confounded
with P. Rathkei, to which species it bears a rather close resemblance.
Distribution. Central part of Europe: Upper Pfaltz, Bohemia, Saxony.
ia, Tyrol.
Gen. 5. MetOpOnOFthUS, B.-Lund, 1879.
Syn: Porcellionides, Miers.
Generic Characters. Body oblong, subdepressed, with very thin integu-
ments. Cephalon with the lateral lobes very small,
frontal lobe obsolete. Side-
plates of mesosome but very slightly prominent. Metasome abruptly contracted,
with the epimeral plates of 3rd to 5th segments sub-appressed ; last segment
comparatively short, triangular. Eyes well developed, lateral. Antennula? very
small, with the last joint quite short. Antennae slender and elongated, flagellum
biarticulate. Oral parts nearly exactly as in Porce.llio. Legs slender, and greatly