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plates of only the 2 anterior pairs of pleopoda with air-cavities. Uropoda with
the outer ramus in male nearly twice as long as in female. Colour of dorsal
face leaden grey, the segments of mesosome having on each side of the median
line an assemblage of lighter, wavy stripes ; lower face and legs pale yellowish.
Length of adult male reaching
to 15 mm.
Remarks. The long list of synonyms given above, which could still be
somewhat augmented, proves that this species has been described under many
different names, a fact that may be accounted for, partly by a certain amount
of variability, partly by its occurrence in widely distant parts of the world. Ac-
cording to the great authority of Mr. Budde-Lund, all these supposed species are
in reality spurious, being referable to the well-known European
form P. levels of
Latreille. From the other species of the genus, it may be recognized by its
comparatively broad and smooth body, the form of the side-plates
some, and the greatly produced uropoda, partly also by its colour.
Occurrence. -Though as yet I have no trustworthy knowledge
of the meso-
of the
occurence of this species in Norway, I regard it as beyond doubt that, on a
closer investigation, it will be found to exist somewhere in this country, since its
occurrence otherwise has turned out to be almost ubiquitous. The figures here
given are from Danish specimens kindly forwarded to me from the Zoological
Museum in Copenhagen. According to Mr. Budde-Lund, it is especially found
in cellars beneath bakeries, or in other places where a rather high and uniform
temperature prevails, sometimes also in refuse-heaps close to the towns. It is
said to be not particularly agile in its movements.
Distribution. Sweden, Denmark, Germany, Belgium, Britain, France, Austria,
Spain, Italy, Dalmatia, Greece, Turkey, Tunis, Syria, Egypt, Turkestan, Madeira,
Azores, North America, Mexico, West-Indies, Peru, Brazil, Chili, Pacific Islands.
6. Porcellio Ratzeburgii, Brandt.
(PI. LXXX, fig. 1.)
Porcellio Ratzeburgii, Brandt, Consi,. monogr. Crust. Isop. terrestr., p. 13, fig. 3.
Syn : Porcellio nemorensis, Koch.
quercuum, Sclmitzl.
lugubris, Koch.
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