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shorter than the cephalosome, and rather densely setiferous at the end of the
joints, 1st joint about the length of the remaining joints combined, olfactory
filaments 5 in number. Inferior antennae but little shorter than the superior,
though somewhat narrower. Chelipeds very strong, hand in female oblong oval
and exceeding in length the carpus, both fingers provided
inside with an obtuse
tubercle; that in male considerably larger, with the fingers distinctly forcipate.
1st pair of pereiopoda longer than the others, dactylus Inarticulate and subulate
in shape the ; succeeding ones with the carpal joint somewr hat expanded and armed
with several strong denticles, dactylus in the 3 posterior pairs very strong,
hooked and armed inside in their outer part with comb-like denticles. Uropoda
about the length of the last 2 segments of metasome combined, 3-articulate and
rather densely setiferous, middle joint the longest, terminal joint rather short.
Body whitish, variegated on the dorsal surface with a dark brownish pigment form-
ing on the cephalosome a close reticulation, on the segments of mesosome, inter-
rupted transversal bands. Length of adult female 5 mm.,
Remarks. - - This form has been recorded by Kroyer, as early
of male somewhat less.
as in 1842,
under the above name, whereas Rathke's description of his Crossurus vittatus dates
from the succeeding year. According to the rules of priority therefore, the specific
name proposed by Kroyer ought to be preferred to that of Rathke. The T. Cavolini
of M.-Edw. is very closely allied to the present species, and the only, in any
way essential difference I have found in examining a single specimen
species, is that the uropoda
are 4-articulate instead of 3-articulate.
of that
Occurrence. - - Rathke found this form on oysters at Molde. It has sub-
sequently been observed at Christiansund by v. Diiben,
and on the south coast
by Orsted. My late father found it at Floro and Manger. I have myself ob-
served it rather plentifully in a small bay at Korshavn, south of Bergen, where
it occurred in quite shallow water among grass. At Haugesund, farther south,
I have found it occasionally in weedy pools left by the tide.
Distribution. -- Oresund (Kroyer). British Isles (Sp. Bate), Atlantic coast
of North America (Harger).
Gen. 2. Heterotanais, a. o. Sars, isso.
Generic Characters. Body comparatively short and thick, slightly depressed,
and exhibiting a rather different appearance in the two sexes. Metasome nor-
mally developed, with all 6 segments well defined. Eyes distinct, placed, as in