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og hos Sol. endeca, hvor de ere mere ovale, ligge tæt
taglagte.
Odontophoren hos Sol. furcifer, Tab. IX, fig. 9, e,
adskiller sig ikke fra de øvrige Arters; den har
Grundformen for Slægten Solaster.
Randpladerne ere stillede i to Rækker, den ene
tilhørende Ryg-, den anden Bugfladen.
De dorsale Randplader, Tab. IX, Fig. 10, c. 11, c,
ere smaa, lidt ovale, tynde Plader, der paa den inderste
Del af Armen ligge lidt fra hverandre, men nærme sig alt
mere og mere, jo længere de naa frem mod Enden, indtil
de ganske slutte sig sammen. De have paa den øvre Flade
en liden Fordybning, der tjener til Ledflade for den
dorsale Paxillerække langs Randen, imedens den undre Flade
er jævn og hviler paa en liden Del af den tilsvarende
ventrale Randplade, bundet til denne ved stærkt Bindevæv.
De ventrale Randplader, Tab. IX, Fig. 9, c. 10, a.
11, b, ere lidt mere aflange og lidt større end de
dorsale; deres undre Flade fæster sig med en liden Del
til den dorsale Randplade og afgiver Ledfladen for den
ventrale Paxillerække; deres øvre Flade er lidt konkav og
hviler paa den undre, afrundede Rand af den tilsvarende
Adambulacralplade, Fig. 10, b.
Skelettet ligner saagodtsom ganske det hos Sol.
papposus. Ambulacralpladerne have maaske lidt bredere
Tver-processer, ligesom Adambulacralpladerne ere lidt tyndere,
men forøvrigt kunne vi ingen Forskjel finde.
Af det her anførte maa det vel erkjendes, at
Solaster furcifer ikke har noget høiere udviklet Hudskelet, end
flere af de øvrige Arter af Slægten, at Rahdpladerne ikke
i nogen væsentlig Grad adskille sig fra dem hos Sol.
glaci-alis, endeca, affinis og papposus, at Skelettet ingen synderlig
Afvigelser frembyder, og at der, som Følge heraf, ingen
Grund er til at opstille nogen ny Slægt for den.
Vi formene nu saaledes at have tilstrækkelig
begrundet den af os tidligere udtalte Anskuelse, at Slægterne
Crossaster og Lophaster ikke lade sig opretholde.
Førend vi slutte disse Bemærkninger, skulle vi, efter
de af os anstillede Undersøgelser, tro os berettigede til
yderligere at udvide Karaktermærkerne for Slægten Solaster.
Legemet 5- eller flerarmet, overalt besat med
penselformede Paxiller; imellem disse Tentakelporer. 2 Rækker
mere eller mindre udviklede, men af Huden skjulte
Randplader. Anus central.
as the calcareous plates in Sol. endeca, which are more
ovate in form; both lie closely imbricate.
The odontophore in Solaster furcifer (Pl. IX, fig. 9 e),
does not differ from that of the other species, and has the
normal form pertaining to the genus Solaster.
The marginal plates are ranged in two series; one
pertaining to the abactinal, and the other to the actinal
surface.
The dorso-marginal plates (Pl. IX, fig. 10, c. 11, c)
are thin, small, slightly oval plates, which in the diskal
part of the ray, are slightly parted from each other, but
close, gradually, more and more upon each other towards
the extremity of the ray, until they at last unite.
They have a small cavity on the superior surface,
which serves as an articulatory surface for the dorsal
pax-illar series along the margin; whilst the inferior surface is
even, and rests upon a small portion of the corresponding
ventro-marginal plate, and is secured to it, by strong con.
nective tissue.
The ventro-marginal plates (Pl. IX, fig. 9, c. 10,a. 11,6)
are a little larger and a little more oblong than the
dorso-marginal plates. Their inferior surfaces, besides being secured to
the dorso-marginal plates by a small portion, furnish, as
well, the articulatory surfaces for the ventral paxillar
series. Their superior surface is slightly concave, and rests
upon the inferior rounded margin of the corresponding
adambulacral plate (Pl. IX, fig.( 10, b).
The skeleton, almost, quite resembles that of Solaster
papposus. The ambulacral plates have, perhaps, somewhat
broader transverse processes; whilst, the adambulacral
plates are a little thinner, but we observed no difference,
otherwise.
From what has been stated here, it must be
admitted, that Solaster jurcifer has not any higher developed
skeleton, than several of the other species of the same
genus, and that the marginal plates do not in any special
degree differ -from those of Solaster glacialis, endeca, affinis
and papposus; further, that the skeleton presents no
particular divergencies, and that there is, consequently, no reason
to originate a new genus for it.
"We believe, that we have, now, sufficiently
substantiated the view we have previously expressed viz. that the
genera Crossaster and Lophaster cannot be maintained.
Before we close these remarks, we shall, as the result
of the examinations we have instituted, consider ourselves
entitled to further extend the characteristic features of the
genus Solaster.
The body is 5-rayed, or sometimes has more rays.
It is everywhere beset with penicilliform paxillæ, having
tentacular pores seated betwen them. There are two series
of more or less developed marginal plates, but these are
concealed by the integument. The anus is mesial.
Den norske Nordhavsexpedition. Daiiielssen og Koren: Asteroidea.
281
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