Forekomst og Levevis. 
Den her omhandlede merkelige Dyreform fore- 
kommer ikke sjelden langs vor hele Kyst, fra Chri- 
stianiafjorden til Vadse, men synes idethele at op- 
trede baade hyppigst og kraftigst udviklet i vor 
arktiske Region. I stor Mengde har jeg saaledes 
fundet den paa en Plads i Lofoten, Brettesnes, hvor 
mange hundrede Individer indsamledes i Lobet af et 
Par Dage, og ogsaa ved Finmarken har jeg paa sine 
Steder truffet den i meengdevis, Den pleier at holde 
til paa maadeligt Dyb, fra 10 til 30 Favne, og helst 
paa saadanne Steder, hvor Bunden er dekket af 
forraadnende Tangarter, hvoraf den for en veesent- 
lig Del synes at ernere sig. Ligesom Tilfeldet er 
med flere andre Crustaceer, synes Hannerne kun til 
visse bestemte Tider af Aaret at opnaa fuld Slegts- 
modenhed, og optreeder da kun ganske enkeltvis. Der- 
imod er endnu ikke slegtsmodent udviklede Hanner - 
at finde til enhver Tid af Aaret og nesten i samme 
Antal som Hunnerne. I Maaden at bevege sig paa, 
ligesom i sin hele ydre Habitus, har dette Dyr en 
umiskjendelig Lighed med en colossal Copepode; 
navnlig er den habituelle Overensstemmelse med 
visse Harpacticider meget paafaldende. Ligesom hos 
disse sidste, er Legemet overordentlig boieligt, navn- 
lig i dorsal Retning, og kan ofte krummes saa steerkt, 
at Halegrenene kommer i Contact med Pandepladen. 
Bevegelsen sker stodvis ved kraftige og temmelig 
rythmiske Slag af Svommefodderne, hvorved Lege- 
met drives frem med temmelig betydelig Fart. De 
slegtsmodne Hanner er overotdentlig raske i sine 
Beveegelser og foretager ofte lengere Udflugter i 
Vandet. Derimod holder Hunnerne og de endnu ikke 
fuldt udviklede Hanner sig i Regelen ved Bunden 
og beveger sig her mellem Bundmaterialet, ialmin- 
delighed paa Siden. De forstaar herunder med stor 
Behendighed at skjule sig mellem Mudret eller de 
hensmuldrende Tangrester, som bedekker samme, 
saa det slet ikke er saa let at finde dem frem, trods 
den ikke ubetydelige Storrelse. Lettest opdager 
man dem ved at slaa det optagne Bundmateriale ud 
i et fladt Kar, med en ubetydelig Kvantitet af Sjo- 
vand. De tilstedeverende Exemplarer vil da, iser 
naar man rorer lidt om i Bundsatsen, snart vise sig 
paa Overfladen af Vandet, og da de i Lighed med 
forskjellige andre Crustaceer ikke formaar at komme — 
ned i Vandet igjen, efterat de forst er komne i Be- 
rorelse med Luften, kan de med Lethed opsamles i 
levende Tilstand. Bringer man et helst yngre In- 
divid i en passende Kvantitet Sjovand under Mikro- 
skopet, kan man saa noiere studere de forskjellige 
Livsytringer og kan gjennem de halvt gjennemsigtige 
Integumenter observere Hjertets Pulsationer, Tar- 
mens perestaltiske Bevegelser og Branchialfoddernes 
Spil. Disse sidste, der ingensomhelst Inflydelse har 
paa Locomotionen, vil man i Regelen finde i en 
Distribution and habits. 
The remarkable animal form spoken of here 
appears not rarely along our entire coast, from the 
Christianiafiord to Vadse, but seems, on the whole, 
to appear most frequently, and most powerfully de- 
veloped in our Arctic region. I have thus found it 
in great abundance at a place, Brettesnes in Lo- - 
foten, where many hundreds of individuals were col- 
lected in the course of a couple of days; and also 
in Finmark I have, in certain places, met with it 
in great abundance. It is accustomed to keep itself 
at a\moderate depth, from 10 to 30 fathoms, and 
preferably in those places where the bottom is co- 
vered with decomposing sea-weed of which it appears, 
to a material extent, to nourish itself.’ Like what 
is the case with several other Crustaceans, the males 
appear to only attain full power of reproduction at 
certain fixed seasons of the year, and are then met 
with only quite solitary. On the other hand, not 
fully reproductively ripe developed males are to be 
found at all seasons of the year, and almost in 
equal number to the females. In manner of 
movement, as well as in entire external habitus 
this animal has an unmistakable likeness to a 
colossal Copepod, especially is the habitual agree- 
ment with certain Harpacticide very striking. Like 
as in those last, the body is extraordinarily flexible, 
especially in dorsal] direction, and may ofen be so 
strongly bent that the caudal branches come into 
contact with the frontal plate. The movement takes 
place in jerks, with powerful and tolerably ryth-~ 
mical strokes of the swimming feet, by which the 
body is drawn forwards with pretty considerable 
speed. The reproductively ripe males are extra- 
ordinarily active in their movements, and frequently 
make long excursions in the water. On the other 
hand, the females and the not yet fully developed 
males remain, as.a rule, at the bottom, and move 
here among the material of the bottom, generally 
on the side. In doing this they understand to con- 
ceal themselves with great dexterity in the mud, or 
the decomposing remains of sea-weed which covers 
it, so that it is not at all easy to search them out, 
in spite of the not inconsiderable size. We find 
them easiest by pouring the collected bottom mate- 
rial into a flat vessel, along with an inconsiderable 
quantity of sea-water. The specimens present will 
then, especially if the bottom stuff is stirred a little 
up, soon show themselves on the surface of the 
water, and as they, like several other Crustaceans, 
are unable to swim downwards in the water again 
after they have first come into contact with the air, 
they may with ease be collected in the live state. 
If we place, preferably a young individual, in a 
suitable quantity of sea-water, under the microscope, 
we can then more closely study the various features 
