128 
traadformig, noget kortere end Skaftet og sammensat af 
circa 14 Led. 
Munddelene kunde ikke noiere undersoges paa det 
eaeste foreliggende Exemplar. 
lste Fodpar (Fig. 28) er betydelig kortere end de 
0vrige og uddannet til et. Slags Griberedskaber, skjondt af 
mindre kraftig Bygning end hos den typiske Art. Basal- 
leddet er meget smalt og n ms ten saa langt som alle de 
ovrige tilsammen. 4de Led er noget, skjondt ikke meget 
opsrulmet og i den indre Kant forsynet med 3 stive Bor- 
ster. Sidste Led er meget bevsegeligt forbundet med dette 
og kan slaaes ind mod samme; det ender med en staerk, 
tydeligt 2-leddet Klo. 
De ovrige Fodpar er alle af ens Udseende, segte 
Gangfodder og af en saerdeles spiukel Bygning. De til- 
tager noget i Lsengde forfra bagtil og'viser sig ordnede i 
2 Sset, idet de 3 forreste er adskilte fra de 3 bagerste ved 
et meget betydeligt Mellenmun, der indtages af det ovenfor 
omtalte mediane Kropsafsnit. 
Halevedhsengene (se Fig. 29) er meget smaa og synes 
kun at bestaa af et enkelt konisk Led, der ved Spidsen 
liar nogle fine Borster. 
Dyrets Farve er ensformig skidden graalig, omtrent 
som det Mudder, hvori det lever. 
Lsengden af det undersogte Individ er kun 4.20’™. 
Forekomst og Uclbredning. Et enkelt Exemplar af 
denne distincte Art optoges i Bundskraben under Expedi- 
tionens 2det Togt i Havet Vest af Lofoten fra et Dyb af 
778 Favne. 
Om Artens Udbredning kan selvfolgeligt intet med 
Bstemthed anfores; men da den ovennsevnte Station tilhorer 
deu kolde Area, er der al Bimelighed for, at den er en 
segte arktisk og for de nordlige Have eiendommelig Form. 
Fam. 2. Munnopsidee, Lilljeborg. 
(Isopoda remigantia, G. 0. Sars) 
Bemserkninger. De til denne Familie liorende Iso- 
poder udmserker sig i hoi Grad ved den mserkvrerdige Byg- 
ning af de 3 bagerste Fodpar, der er meget ulige de ovrige 
saavel i Form som Function, idet de er uddannede til 
nuegtige Svommeredskaber, hvormed Dyret kan, ofte med 
stor Fart, bevsege sig frit om i Yandet i baglaends Retning. 
Denne Character er i Yirkeligheden saa eiendommelig og 
ulig alt, hvad vi hidtil kjendte, at jeg i Begyndslsen blev 
forledet til lierpaa at grundc en ganske egen Isopodetribus, 
simple-cylindric. The flagellum is filiform, somewhat shorter 
than the peduncle, and composed of about 14 articulations. 
The oral appendages could not be submitted to close 
examination in the sole specimen obtained. 
The 1 st pair of legs (fig. 28) are considerably shorter 
than the rest, and developed as a kind of prehensile organs, 
though less powerful in structure than in the typical species. 
The basal joint is exceedingly slender, and well-nigh as 
long as all the others taken together. The 4th joint is 
somewhat, though not much, swollen, and furnished along 
the inner margin with 3 stiff bristles. The last joint is 
very movably connected with the latter, and admits of 
being bent in towards it; this last joint terminates in a 
strong, distinctly bi-articulate claw. 
The remaining pairs of legs are all uniform in ap- 
pearance, being true pereiopoda, and exceedingly slender 
in structure. They increase somewhat in length posteriorly, 
and are arranged in 2 series, the 3 anterior lining separated 
from the 3 posterior pairs by a very considerable interspace, 
occupied by the aforesaid medial section of the body. 
The caudal appendages (see fig. 29) are very small, 
and would appear to consist of but one conical joint, fur- 
nished at the extremity with a few delicate bristles. 
The colour of the animal is a uniform dirty grey, 
much the same as that of the mud in which it lives. 
Length of the specimen examined only 4.20’""’. 
Occurrence and Distribution. — A single specimen 
of this distinctly characterized species was brought up in 
the dredge on the 2nd cruise of the Expedition, in the open 
!j sea west of Lofoten, from a depth of 778 fathoms. 
Respecting, the distribution of the species, nothing can 
of course be stated with certainty ; but the Station at which 
the specimen was taken being in the cold area, there is 
every reason to regard the animal as a true Arctic form, 
peculiar to the fauna of the Northern Seas. 
Fam. 2. Munnopsidee, Lilljeborg. 
(Isopoda remigantia, G. O. Sars) 
Remarks. — The Isopoda belonging to this family 
are very prominently distinguished by the remarkable struc- 
ture of the 3 posterior pairs of legs, differing most essentially 
as they do alike in form and function, being developed to 
powerful natatory organs, by means of which the animal, 
often with great rapidity, can move through the water in a 
backward direction. This character is indeed so peculiar 
and unlike anything hitherto observed, that at first I felt 
disposed to establish from it a distinct tribe of Isopods, 
