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2. Astaeilla arietina, G. 0. Sars.
(PI. XXXVII, fig. 1.)
Aslaallct firu'tiiift, G. O. Sars. Oversigt af Novges C'rustaci-cv I, p. 62, PI. 2, fig. 2.
Specific Characters. Very like the preceding species as to the general
form of the body, and the structure of the several appendages, but differing in
the strange development of some of the dorsal tubercles, those of the cephalon
assuming the appearance of a pair of very conspicuous, acute horns pornting
slightly forwards, and somewhat divergent. Middle segment of mesosome not quite
twice as long as the preceding part of the body, and exhibiting in its anterior
part, dorsally, 4 remarkably strong pyramidal prominences, disposed in pairs; the
posterior part of the segment very rough, owing to the presence
of numerous
obtuse tubercles. Colour greyish, with irregular dark brown patches. Length of
adult female 19 mm.
Remarks. This form is very closely allied to ^1. longicornis, and I have
indeed been in some doubt as to whether it should not more properly be regarded
as a more accidental variety of that species. But. on going through the vast material
of ^4. longicornis at my disposal. I have failed to detect any sign of the peculiar
development of the dorsal tubercles characteristic of the present species.
Occurrence. The only place where this form lias come under my no-
tice, is Tjernagel in the outer part of the Hardanger Fjord. From a depth of
GO to 100 fathoms, stony bottom. I there took up in the dredge 2 adult specimens,
female and male, the former with the inferior antenna 1
densely
clothed with
the adhering newly-hatched brood. The male had much the same appearance
as that of A. luinjicorn'is, though the tubercles of the cephalon were quite con-
spicuous, whereas in the male of .4. lonyicorni* they are always wholly absent.
3. Astaeilla affinis,
(I'l. XXXVII, fig. 2.)
G. 0. Sars.
A:I-IIII-IIK
ciffinls, G. O. Sars, Nyc Dybvandscrustaceer Ira Lofoten. ("Mir. Vnl. Selsk. Forli. 186!.
1>.
163.
Specific Characters. Body of female comparatively
less slender than in
the '2 preceding species, and but slightly tubercular. Middle segment of mesosome
not nearly twice as long ;is the preceding part of the body, and exhibiting, quite
in front, 2 juxtaposed dorsal tubercles of somewhat larger size than the others.
Eyes comparatively smaller than in the 2 preceding species. Superior antenna 1
with the riagellum twice as long as the 2 preceding joints combined, and carrying
only 5 olfactory iilamcnts. Inferior antenna1 with the tlagellum not attaining l
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