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10
Af den ovenfor beskrevne Asterias Qunneri fandtes 1
Exemplar, paa hvilket Skiven var noget mindre, Armene
kortere, deres Rygflade rigere besat med stærkere Pigge,
og Hudskelettet meget stærkere bygget, saa at Maskenettet
var tydeligt at se uden nogen Præparation.
Af denne temmelig udprægede Varietet, der synes at
være en Overgangsform til Asterias Linckii, have vi
erholdt fra Professor Sven Lovén to mindre Exemplarer fra
det kariske Hav, og som vare bestemte af Dr. Stuxberg
’som Asterias Linckii, men hvorfra den dog i væsentlige
Punkter adskiller sig.
Fra det naturhistoriske Museum i Kjøbenhavn have vi
igjennem Dr. Lütken faaet udlaant 2 Exemplarer fra
Spitsbergen, hvilke foreløbig vare signerede Asterias stellionura;
ifølge vore sammenlignende Undersøgelser ere de Asterias
Qunneri.
Of the above described Asterias gunneri, one
specimen was discovered, upon which the disk was somewhat
less; the rays shorter, and their abactinal surface more
numerously occupied by strong spines. The dermal skeleton
was much stronger in construction, so, that without any
treatment, the reticulation was distinctly visible.
Of this tolerably marked variety, which appears to
be a transition-form to Asterias linckii, we have obtained
from Professor Sven Lorén, two small specimens from the
Kara Sea, and which were diagnosed as Asterias linckii,
by Dr. Stuxberg, but from which they differ, however, in
important points.
From the Museum of natural history in Copenhagen,
we have obtained through Dr. Lütken, the loan of 2
specimens from Spitzbergen, which where provisionally diagnosed
as Asterias stellionura. According to our comparative
examination they are Asterias gunneri.
Asterias hyperborea, n. sp.
Tab. m, Fig. 1—7.
Legemet 5-armet med hvælvet Ryg og flad Bug. Den
lille Radius forholder sig til den store som 1 : 6.
Skiven, 22™m i Diameter, er hvælvet, rigelig besat med
stumpe, korte Pigge, der ere afvexlende tykke og tynde;
men alle omgivne af 2 ovenpaa hinanden staaende Krandse
af tæt grupperede, korsformige Pedicellarier, Fig. 1.
Mad-reporpladen lille, aflang, flad, sidder 4mm ovenfor, lidt til
Siden af Armvinkelen.
Armene ere 55""" lange, ganske lidt indknebne ved
Grunden, men ere 15mm brede strax nedenfor og aftager
jævnt i Tykkelse til den spidse Ende. Armenes Rygside
er konvex, besat med temmelig tætstaaende, tykke, noget
stumpe, omtrent lmm høie Pigge, der ere omgivne af 2—3
ovenpaa hinanden staaende Krandse af korsformede
Pedicellarier, Fig. 1. 3. 4. Henimod Siderne ordne Piggene
sig i regelmæssige Rækker, ligesom de tiltage baade i
Længde og Tykkelse, Fig. 1. Af disse Rækker ere to
stærkt fremtrædende, danne egentlig Grændsen imellem Ryg
og Bug, og kunne betragtes som Randpigge, hvoraf de,. der
sidde i Rækken nærmest Bugfladen, ere dobbelt saa lange
(12mOT) som Rygpiggene, have en meget bredere Basis end
disse, og omgives kun paa den ydre Halvdel af korsformede
Pedicellarier, Fig. 2. Overalt imellem Piggene ere
Rummene optagne af 1—3 Tentakelporer; ingen Pedicellarier
findes der.
Asterias hyperborea, n. sp.
PI. III, fig. 1—7.
The body, is 5 rayed, and has an arched abactinal
surface, and flat actinal surface. The disk radius bears to
the brachial radius, the proportion of, as 1:6.
The disk is 22mm in diameter, convex, and occupied
by numerous, short, blunt spines, which occur, alternately,
stout and slender, and, these, are environed by 2 wreaths
of closely grouped cruciform pedicellariæ, disposed one above
the other (fig. 1). The madreporite is small, ovate, flat,
and seated 4mm above, and slightly to the side of the
inter-brachial angle.
The rays are 55mm long, quite slightly constricted at
the origin, and are 15""" in breadth immediately beyond
the constriction, and thence, taper uniformly to the pointed
extremity. The abactinal surface of the rays is convex,
and bedecked, with rather close-set, stout, and somewhat
blunt spines, about 1""" long; these are encompassed by
2—3 wreaths of cruciform Pedicellariæ disposed one above
the other, (figs. 1, 3, 4). Towards the lateral surfaces,
the spines become arranged in regular series, and increase,
also, both in length and thickness (fig. 1). Of these series,
two are strongly prominent, forming indeed, the margin
between the abactinal and actinal surfaces; they may be
considered as marginal spines, of which those seated in
the series nearest to the ventral surface, are twice as long
(12mm) as the dorsal spines, and posess a much broader
base than these, and are encompassed, also, only on the
exterior half, by cruciform pedicellariæ (fig. 2). The
interspaces between the spines, are, everywhere, occupied by
1—3 tentacular pores; no pedicellariæ are visible in this
situation.
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