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162
Occurrence. According to Mr. Budde-Lund, this form was many years
who found it at Molde.
ago observed here in Norway by Prof. Lilljeborg,
Some few specimens are, moreover, preserved in our University Museum from
earlier times, having been collected by the late Dr. A. Boeck in the neighbourhood
of Christiania, and I have also recently received this form from Trondhjem
through the kindness of Conservator Storm. I have myself found it very
frequently in many places around Christiania, as also at Drobak and Laurvig,
beneath moist leaves, stones and pieces of wood, especially in very shady places.
A certain degree of moisture seems to be indispensable to its existence, and there-
fore in dry places fully exposed to the sunshine,
it is never met with. When
disturbed, it runs about with great agility to conceal itself, and is thus only
with difficulty got hold off, and being very fragile, it is easily damaged when
caught. It is very curious that among the numerous specimens collected, I have
failed to detect any male specimen. Perhaps
species are so very inconspicuous as to escape attention.
geria,
the male sexual characters in this
Distribution. Sweden, Denmark, Germany, France, Britain, Spain, Al-
North America.
2. Triehoniseus pygmaeus, G. 0. Sars. n. sp.
(PI. LXXU, fig. 2.)
Specific Characters. Body rather narrow, oblong, fully 3 times as long as it
is broad, dorsal face rather convex and rough, the roughness arising from numerous
small tubercles arranged in transversal rows. Cephalon
rounded, with the lateral
lobes extremely minute, front rather arcuate. Lateral parts of the segments of meso-
snme edged with small appressed spikes; those of the 3 posterior segments, as
in T. pusillus, more prominent than the proceeding ones, and terminating in re-
curved conical points. Metasome rather narrow, and of a similar structure to
that in T. pusillus] last segment with the terminal expansion gradually tapering,
and narrowly truncated at the tip, carrying 2 rather long apical hairs. Anten-
nuloe with the last joint scarcely longer than the 2nd, and only provided with 3
sensory filaments. Antenna- comparatively less slender than in T. puxillns. tiagel-
luiii scarcely attaining the length of the last peduncular joint, and composed of
only :> articulations. Legs comparatively shorter than in the type species, but
otherwise of a similar structure. Inner ramus of 1st pair of pleopoda in male
greatly produced, with the terminal joint narrow knife-shaped; that of 2nd pair
Inarticulate, proximal joint very short, distal joint long and slender, styliform.
Uropoda rather -hort. with the rami nearly equal, and but little longer than the