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oftest shatteret med større uregelmæssige Pletter eller Skjolde
af en mørkere brun Couleur.
Længden af de største Exemplarer er, maalt fra
Enden af 2det Par Føleres Blad til Spidsen af det midterste
Halevedhæng 130™", og den her omhandlede Form staar
saaledes neppe tilhage i Størrelse for nogen af de tidligere
bekjendte Arter af Slægten.
Udvikling. De under Hunnernes Bagkrop fæstede
iEg er (se Fig. 2) forholdsvis af temmelig betydelig
Størrelse. hvilket tor tyde hen paa, at Ungernes Udvikling er
forbunden med en mindre fuldstændig Metamorphose end
hos de øvrige Orangmiider. Hos ingen af de erholdte
Exemplarer var dog Æggenes Udvikling saa vidt fremskreden,
at dette med Sikkerhed kunde constateres.
Ganske unge Individer af lain 16—18 Mill.’s Længde
er af noget slankere Kropsform end fuldt udvoxede Dyr
og har Pandehornet forholdsvis større og de tornformige
Fortsatser paa Legemet skarpere fremtrædende. Saavel
paa Rygskjoldets som Bagkroppens Overflade findes spredte
og temmelig lange Haar.
Forekomst og Levevis. I vore Have er denne Art
en ægte Dybvandsform, som neppe nogensinde her træffes
før i en Dybde af omkring 1UU Favne, medens den gaar
ned lige til 459 F. og maaske endnu dybere. Derimod
synes den ved Kamtschatka at leve paa betydelig grundere
Vand, da den her. ifølge Tilesius fanges i stor Mængde nær
Kysten af de Indfødte, der anvender den til Næring.
Ligesom de øvrige Crangonider er den en udpræget Bundform,
hvilket tydeligt nok fremgaar af dens hele Organisation og
navnlig af de stærkt incrusterede Integumenter. der giver
Legemet en betydelig specifisk Vægt og neppe tillader Dyret
at gjøre ret lange Udflugter i Vandet. De af os indsamlede
Exemplarer var ogsaa kun lidet livlige i sine Bevægelser
og holdt sig fordetmeste rolige paa Bunden af de Kar,
hvori de opbevaredes for nærmere Observation.
Udbredning. Saavel de til Grund for Tilesius’s som
Owen’s Beskrivelser liggende Exemplarer var fra
Kamtschatka, som tidligere var det eneste bekjendte Findested
for nærværende Art.
I et nylig af Dr. Stuxberg udgivet interessant Skrift
betitlet: "Evertebratfaunaen i Sibiriens Ishav" anføres
imidlertid denne Art at være fundet under Nordenskjölds
Expedition 1876 i det kariske Hav paa et Par Lokaliteter.
Under vor Expedition har vi taget den paa 6
forskjellige Stationer, hvoraf de 4 tilhorer Havet omkring
Spitsbergen, medens de 2 ovrige ligger vidt adskilte, den
ene ved Jan Maven, den anden i Havet udenfor vor Vestkyst.
Dens for Tiden bekjendte geografiske Udbredningsfelt
strækker sig herefter fra Kamtschatka og Behringsstrædet
vestlig idetmindste til 8° V. L. og fra den 63de til den
80de Bredegrad.
Den norske Nordliavsexpedition. G. O. Sars: Crustacea.
a rule relieved with comparatively large irregular spots or
patches, of a darker brown colour.
The length of the largest specimens, measured from
the extremity of the scale of the 2nd pair of antennae to
the tip of the telson. reaches 130°’™; and hence the form
here treated of can, as regards size, hardly yield precedence
to any of the previously known species of the genus.
Development. — The eggs attached beneath the
abdomen of the females (see fig. 2) are comparatively large,
a circumstance from which, perhaps, we may infer, that
the development of the young animals is attended with a
less complete metamorphosis than in any of the other
Cran-gonidce. In none, however, of the specimens collected had
the ova attained a stage of development that would admit
of confirming the assumption with certainty.
Very young animals, not exceeding 16—18 millimetres
in length, have the body of a somewhat more slender form
than full-grown individuals, the rostrum, too. relatively larger,
and the spiniform prolations on the body more sharply
defined. Both on the carapax and the surface of the
abdomen are seen scattered hairs of considerable length.
Occurrence and Habits. — In the North Atlantic, this
species is a true deep-sea form, rarely, if ever, met with at a
depth less than about 100 fathoms, though elsewhere it descends
to 4511 fathoms, and possibly still deeper. On the other hand,
off the coast of Kamtschatka it would appear to inhabit much
shallower water, being there, according .to Tilesius, taken
near the coast in great abundance by the natives, who
consume the animal as food. Like all other Orangomdæ.
it is a well-marked bottom-form, a fact sufficiently apparent
from its whole organization, and in particular from the
thickly incrusted integuments, which give to the body a
considerable specific weight, and can hardly admit of the
animal travelling far through the water. Nor were the
specimens we collected particular}’ brisk iu their movements,
keeping as they did during the greater part of the time
quietly at the bottom of the vessels in which they were
preserved for closer examination.
Distribution. — The specimens to which the
descriptions both of Tilesius and of Owen refer, were from oft
Kamtschatka. formerly the only known habitat of the
present species.
According to an interesting paper lately published by
Dr. Stuxberg. bearing title: — "Evertebratfaunaen i
Sibiriens Ishav" (The Evertebrate Fauna in the Polar Seas of
Siberia), this species would appear to have been taken on
Nordenskjöld’s Expedition in 1876. from the Kara Sea.
in one or two localities.
During the course of our Expedition, we obtained
the animal at 6 different Stations. 4 in the sea surrounding
Spitzbergen, the 2 others lying wide apart, one at Jan
Mayen, the other off the western shores of Norway.
Hence, the geographical distribution of the species as
yet known, ranges in a westerly direction from Kamtschatka
and Behring’s Strait at least to long. 8» W.. and from the
63rd to the 80th parallel of latitude.
4
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