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body, or equalling about the first 5 segments of mesosome combined, slightly
widening behind, terminal segment large, oblong oval and very smooth, tip obtusely
rounded. Superior antennae almost attaining the length of the cephalosome,
basal joint about the length of the other 3 combined, terminal joint comparatively
short and obtusely blunted at the tip. Chelipeds rather strong, hand oblong
oval and longer than the carpus, lingers shorter than the palm, the immovable one
minutely serrulate inside. The 3 posterior pairs of pereiopoda considerably more
strongly built than the 3 anterior ones, and having the outer joints
armed with
ciliated spines, basal joint remarkably constricted at the base. TJropoda very short,
inner ramus conical, biarticulate, and tipped by long diverging setse, outer ranius
extremely minute, tuberculiform, though well defined from the basal part. Length
2.85 mm.
Remarks. From 8. ardophtjlcu' of Norman & Stebbing. the Norwegian
species may be at once distinguished by its much more elongated body and the com-
paratively larger size of the metasome. A few specimens, however,
are of con-
siderably shorter form, but as in all of these there are distinct traces of pleo-
poda, they are, I believe, of the male sex, though probably not yet sexually mature.
Occurrence. I have found this peculiar Tanaid in several places, both
on the south and west coasts of Norway, in depths ranging from 50 to 200 fa-
thoms. It extends northwards to Selsovig, situated just within the polar circle.
Gen. 9. Anarthrura, G. o. Sars, isso.
Generic Characters. Body elongated, subdepressed, with rather thin,
semipellucid integuments. Cephalosome comparatively short and obtusely trun-
cated in front. Metasome in female very poorly developed, narrower than the
mesosome, and without a trace of segmentation; that in male, however, of quite
normal appearance, being divided into 6 well-defined segments. Eyes wanting.
Superior antennge in female 4-articulate, in male but slightly different, though
composed of 5 articulations. Mandibles extremely small and rudimentary, cutting
edge simple, molar expansion wanting. Chelipeds comparatively small, with the
basal part of a somewhat unusual structure, being oval, tumid, and divided into
2 distinct segments, hand rather small, with the palm unusually short. The 3
anterior pairs of pereiopoda rather slender and nearly equal, the 3 posterior
pairs rather different, and considerably more strongly built. Pleopoda in female