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1
foregaaende Led, og som paa Gangfødderne stærkt
chitini-seret. med det ydre Parti krummet og endende i en
sylskarp Spids.
Den ydre Ægmasse (Fig. 1 i), der her som hos alle
andre Pycnogonideer kun findes hos Hannerne, er enkelt
og kageformig, af uregelmæssig afrundet Form og dækker
Størsteparten af Dyrets Bugside. De enkelte Æg er
overordentlig smaa og talrige, omsluttede af en fælles meget
tynd og gjeunemsigtig Membran.
Alle Dyrets Integumenter er meget haarde og tykke,
med en noget ru Overflade, bevirket af talrige smaa
knu-deformige Fremspring. Hist og her findes, navnlig paa
Lemmerne meget korte og spredte Haar, der dog kun ved
stærk Forstørrelse lader sig paavise.
Farven er noget varierende fra lyst hvidgul indtil
mørkt brunlig eller rustfarvet.
Forekomst og Levevis. Ved Norges Kyster
forekommer denne Art meget almindelig ligefra
Christianiafjorden til Vadsø, hyppigst ganske nær Stranden paa ringe
Dyb, men i enkelte Tilfælde ogsaa paa meget større
Dybder, indtil 150 Favne. Ved Lofoten og Finmarken har
jeg taget den ikke ualmindelig i Fjæren under Stene.
I sine Bevægelser er den overordentlig langsom og
træg, endog i høiere Grad end nogen anden mig bekjendt
Pycnogonide. Som oftest ser man den næsten ubevægelig
fastklamret til en eller anden Gjenstand, kun af og til
visende en svag Strækning og Boining af en eller flere af
Gangfødderne. Snabelen synes dog at kunne bevæges temmelig
frit og paa to forskjellige Maader, idet den dels kan bßies
i forskjellige Retninger i Forhold til Hovedsegmentet, dels
til en vis Grad inddrages i eller udskydes fra dette. Som
ovenfor antydet, er der Grund til at antage, at Dyret
idetmindste under visse Omstændigheder fører et Slags
parasitisk Liv. Det er nemlig meget almindeligt, at man finder
denne Form fastklamret til de store paa grundt Vand
levende Actinier, f. Ex. Tealia digitata og erassicornis.
Hvorvidt det er det af disse Dyrs Legeme afsondrede Slim
eller de forskjellige fremmede, til Actiniens Legeme
klæbende Partikler, der tjener den til Næring, er imidlertid
endnu ikke med Sikkerhed godtgjort.
Udbredning. Arten synes at have ell særdeles vid
geographisk Udbredning. Dog er det muligt, at man i
enkelte Tilfælde har forvexlet andre mærstaaende Arter med
denne Fonn. Philippi’s Angivelse af dens Forekomst i
Middelhavet, ved Neapel, anser jeg saaledes for meget
tvivlsom, da den ikke senere af Dohrn er paavist her.
luen vel et Par andre Arter af Slægten. Ligeledes finder
jeg, at Artens Forekomst ved Chili (ifølge Nieolet) og ved
Japan (ifølge Slater) i høi Grad tiltrænger Bekræftelse.
Efter min Formening er den en væsentlig kun for de
nordlige Have eharacteristisk Form, hvad der ogsaa synes at
bekræftes deraf, at den ved vore nordlige Kyster
iahninde-liglied opnaar en kraftigere Udvikling og betydeligere
Størrelse end længere sydpaa. Foruden ved Norge kjendes den
fonn (fig. 1 li). The terminal claw is about as long as
the preceding joint, and, like the ambulatory legs, highly
chitinized, with the outer part curved and terminating in
a most acute point.
The outer egg-mass (fig. I i), which in this animal,
as in all Pycnogonids, we find in the males only, is simple
and cake-like, of an irregular rounded form, and covers the
greater part of the ventral surface. The ova are
exceedingly small and numerous, and invested with a common
very thin and translucent membrane.
All the integuments of the animal are
uncommonly hard and thick, with a roughish surface, occasioned by
numerous small tubercular protuberances. Here and there
occur, more especially on the limbs, very short and
scattered hairs, perceptible only however under a strong magnifier.
The colour is somewhat variable, ranging from a light
whitish-yellow to dark-brownish, or rusty.
Occurrence and Habits. — On the coasts of
Norway this species is very common from the Christianiafjord
to Vadsø, being met with most frequently near the shore
in shallow water, but in some cases at a very considerable
depth, down even to 150 fathoms. In Lofoten and
Finmark I have not seldom taken it on the beach, from
under stones.
In its movements this animal is remarkably slow and
sluggish, more so indeed than any other Pycnogonid I
know of. As a rule you see it firmly clasped to some
object or other, well-nigh motionless, a feeble stretching or
bending now and then of one or more of the ambulatory
legs being the only sign of life. The proboscis however
admits, it would seem, of being moved with comparative
freedom and in two different ways, since, on the one hand,
it can be bent about in various directions to the cephalic
segment, and, on the other, to a certain extent be
withdrawn into or ejected from that part. As intimated above,
there is reason to assume that the animal — at least under
certain conditions — leads a kind of parasitic life. For very
often this form is found firmly clasped to the large Actiniæ
inhabiting shallow water, e. g., Tealia digitata and erassicornis.
Whether it lie the mucus secreted by these animals, or the
different particles of foreign matter adhering to their body,
that serve the Pycnogonid as food, is a question however
not vet finally settled.
Distribution. — This species would appear to have
a wide geographical distribution. Meanwhile, it may be
that in some eases a nearly related form has been
confounded with the present Pycnogonid. Philippi’s statement
as to its occurrence in the Mediterranean, at Naples, I
regard as highly doubtful, Dohrn not having observed
it there, though lie met with two other species of the
genus. Likewise, too, the occurrence of the species on
the coast of Chili (according to Nicolet), and on the coast
of Japan (according to Slater), calls, I certainly think,
for confirmation. In my judgment, it is a form
essentially characteristic of Northern Seas, which indeed
appears from the fact of its attaining a more powerful
development and more considerable size on the northern
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