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3. Eurycope phallangium,
(PI. LXVI.)
G. 0. Sars.
Eurycope phallangium, G. 0. Sars Oni en am>nml Grnppe af Isopoder (Christiania Vid. Selsk.
Forh. 1863), p. 6.
Specific Characters. Body broadly oval, not nearly twice as long
as it
is broad, greatest width in the middle. Cephalon with the frontal part conically
produced. Fifth and 6th segments of mesosome continent in the middle, forming
together a large vaulted plate, deeply emarginated
behind. Caud;il segment com-
paratively small, subpentagonal in form, tip obtusely rounded, lateral edges fringed
with stiff bristles. Superior antennae not much elongated, flagellum composed of
about 10 articulation. Inferior antennae exceedingly slender and elongated, 4 to 5
times as long as the body, the 2 outer joints of the peduncle very narrow and but
sparsely setiferous, flagellum longer than the peduncle. Molar expansion of the
mandibles rather narrow, attenuated distally. Epignath of maxillipeds lanceolate,
without any angle outside. 1st pair of legs comparatively short and rather
strongly built, propodal joint fully as long as the carpal one, the latter slightly
dilated and curved, with a setiferous ridge inside. The 3 succeeding pairs of
legs extremely slender and elongated, more than twice as long as the body, and
having the ischial joint produced to an unusual degree. Natatory legs
with the
carpal joint rather large, obcordate, propodal joint much smaller and narrow oblong
in form, dactylus very much produced, considerably exceeding the propodal joint in
length, and distinctly biarticulate, proximal joint lanceolate, distal one spiniform.
Uropoda with the outer ramus a little longer,
but much narrower than the inner.
Colour of dorsal face light yellowish grey, with a slight reddish tinge. Length of
adult female scarcely exceeding 2 mm.
Remarks. In several respects this species differs rather markedly from
the 2 preceding ones, whereas it exhibits a close relationship to some of the suc-
ceeding species. It is therefore most probable that it will be found advisable to
establish for these species a separate genus. The specific name refers to the ex-
cessively elongated inferior antennae and ambulatory legs.
Occurrence. This species is very common along our whole south and
west coasts, and extends northwards to Hasvig in Finmark. It occurs in depths
ranging from 50 to 300 fathoms, on a bottom consisting of muddy clay. In
spite of its small size and inconspicuous colouring, the animal may be easily
detected on placing a portion of the mud taken up by the dredge in a shallow
vessel, when, like several other small Crustacea, it will Ho at up
to the surface,
without being able to immerge itself again. As, however, the several appendages
of the body are extremely fragile, it is rather a rare occurrence to get a specimen
with all of them uninjured. Though there cannot be any doubt that this form