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116
Gen. 4. DendrOtlOn, G. O. Sara, 1871.
Generic Characters. Body resembling somewhat in shape that in Pleuro-
goninm, being much depressed, with the anterior part
of the mesosome rather
broad, and flanked by strong spines, the posterior abruptly narrowed, with lingtii-
form produced lateral parts. Cephalon comparatively small, and produced on each
side to a remarkable ear-like projection carrying the antennae. Caudal segment
very narrow, lanceolate. Eyes absent. Antennae long and slender, especially the
inferior ones, the peduncle of which is 5-articulate. Mandibles normal,
with well-
developed palp and molar expansion. Legs extremely slender, and rapidly in-
creasing in length posteriorly; 1st pair rather feeble in structure, though distinctly
subcheliform. Uropoda issuing from the dorsal face of the caudal segment, rather
elongated, biramous, outer ramus very small, inner long
and narrow.
Remarks. The present genus is founded upon a very peculiar deep-water
Isopod, which, though in some points differing rather markedly from the other Mttn-
nid(8, yet undoubtedly is referable to that family. The most striking feature is the
insertion of the antennae to ear-like processes of the head, which character indeed
has given rise to the generic name. Another very anomalous character, which
was not fully recognized at first,
is the great development and peculiar origin
of the uropoda, in which respect this genus differs very materially from all other
known Munnidce.
1
Dendrotion ) spinosum, G. 0, Sars.
(PL XLIX.)
Dendrotion spinosum, G. O. Sars, Undersogelser over Hardangerfjordens Fauna. I. Crustacea,
pag. 30.
Specific Characters. Body oblong fusiform in outline, more than twice as
long as it is broad, with the segments very sharply
marked off from each other.
Cephalon comparatively small, sub-quadrangular, slightly widening distally, frontal
edge evenly concave, antennal processes obliquely diverging
and truncated at the
tip. Anterior division of mesosome ob-ovate, gradually widening posteriorly, lateral
parts of the segments angular, and each produced into a strong and very acute
spine, pointing straight
outwards and clothed at the base with scattered hairs.
Posterior division of mesosome abruptly narrowed, with the lateral parts of
the segments linguiformly produced, and decreasing in size posteriorly, each
terminating in a sharp spiniform point, hairy at the base. Caudal segment
l ) By a mistake, the generic name, in the plate, is spelt Pleurotion instead of Dendrotion.