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Indledning’.
Den eiendommelige Gruppe af Arthropoderne, som
ialmindelighed gaar under Benævnelsen Pycnogonider eller
Havspindler, har længe hort til de mindst kjendte Former
indenfor den nævnte store Dyrafdeling, og deres
systematiske Stilling har derfor ogsaa lige til det sidste været
meget tvivlsom. I den nyere Tid er imidlertid vort
Kjendskab til disse Dyr bleven væsentlig udvidet, idet Gruppen
er bleven gjort til Gjenstand for en meget indgaaende
Behandling af forskjellige af vor Tids Forskere. Det er især
2 større Arbeider over disse Dyr, som her maa nævnes,
nemlig Prof. A. Dohrn’s Bearbeidelse af de i Golfen ved
Neapel forekommende Former, og Dr. Hoele’s Report over
det rige under Challenger Expeditionen indsamlede Materiale.
I begge disse betydelige Arbeider er der, foruden
Beskrivelser af en hel Del nye Slægter og Arter, ogsaa leveret
meget vigtige Bidrag til disse Dyrs anatomiske Bygning og
Udviklingshistorie, ligesom ogsaa Forsøg til en præcisere
Inddeling er bleven gjort. Angaaende Havspindlernes
Forhold til andre Arthropoder, er begge disse Forskere enige
i. at de ikke, som før ialmindelighed antaget, kan henføres
til Arachindernes Classe, ligesaalidt som de kan inordnes
under Krebsdyrene, men at de maa danne en egen distinct
Gruppe (Classe) inden Arthropodernes vidtløftige Stamme.
Dette er utvivlsomt rigtigt og vil vistnok blive hævdet af
alle senere Forskere, hvorved ogsaa mange Misforstaaelser
ved Tydningen af de forskjellige Dele, der sammensætter
Pycnogonidernes Legeme, vil blive undgaaet.
Det under Nordhavs Expeditionen indsamlede
Materiale af Pycnogonider er meget betydeligt, og da de
nordiske Former idethele maa siges endnu at være mindre vel
kjendte, har jeg troet at burde levere udførlige
Beskrivelser og Afbildninger af samtlige Arter. Foruden de
under selve Expeditionen erholdte Arter er for
Fuldstændigheds Skyld medtaget de af mig gjennem en lang Række af
Aar ved Norges Kyster observerede Former, hvortil endnu
kommer nogle under Nordenskjolds Expedition 1875 i det
kariske Hav indsamlede Pycnogonider. som velvilligt har
været mig tilsendt til Undersøgelse af Dr. A-. Stuxberg,
Direktør af Gøtheborgs Museum. Det paa denne Maade
tilveiebragte Materiale er saaledes ikke lidet omfattende og
vil kunne give et temmelig fuldstændigt Overblik over
Pyc-nogonidefaunaen i de nordiske og arktiske Have. Det vil
Den norske Nordhavsexpedition. G. O. Sars: Pycnogonidea.
Introductory.
The peculiar group of Arthropods generally passing
under the name of Pycnogonida, or Sea-Spiders, have long
been one of the least known forms in that large division
of animals; and their systematic position has continued up
to the present day very doubtful. Of late years, however,
our acquaintance with these animals has been essentially
extended, the group in question having had exhaustive
treatment by several naturalists of repute. Two rather
voluminous productions on Pycnogonids crave special notice
here, viz., Professor A. Dohrn’s elaborate investigation of
the forms occurring in the Bay of Naples, and Dr. Hoek’s
Report on the rich material from the "Challenger"
Expedition. In each of these important works, we have,
besides descriptions of a number of new genera and species,
most valuable contributions to the anatomical structure and
development of the Pycnogonidea, along also with attempts
in the way of a more precise classification. Concerning
the relation of the sea-spiders to other Arthropods, both
authors are agreed, that we cannot, as formerly for the
most part assumed, refer these animals to the class
Arach-nida, or rather range them under the Crustacea, but that
they must form a distinct group (class) within the
extensive sub-kingdom of the Arthropoda. This view is
unquestionably correct, and will doubtless be taken by all
subsequent naturalists, which cannot fail moreover to
obviate many misconceptions that tend to arise in
determining the various parts composing the body of
Pycnogonids.
The material embracing Pycnogonids from the
Norwegian North-Atlantic Expedition proved very copious;
and the Northern forms being on the whole as yet but
little known, I have seen fit to furnish detailed
descriptions and drawings of all the species. Exclusive of the forms
met with on the Expedition, regard has been paid to those
observed by the author during a long series of years on the
coast of Norway, and also to a few Pycnogonids collected in
the Kara Sea on Nordenskjöld’s Expedition, 1875, kindly
sent nie for examination by Dr. A. Stuxberg, Director of
the Gothenburg Museum. The material thus brought
together is, we see. -sufficiently comprehensive, affording as
it does a good general view of the Pycnogonidian fauna
in the Northern and Arctic Seas. Collation of Dohrn’s
memoir will show at a glance the character of that fauna
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