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22
Pedicellarier ere temmelig store i Forhold til Søstjernens
Størrelse. Basaldelen er bred, den underste Rand stærkt
krummet; Apophyserne stærke og temmelig fremspringende,
Tab. III, Fig. 10, a. Kjæverne ere smale, noget
afstumpede i den fri Ende og meget brede, idet de gaa over i
den forlængede Del, Fig. 10, 6. Den ydre Flade er meget
konvex og forsynet paa dens ydre halve Del med
tætstaaende Vacuoler, Fig. 10, c.. Den indre Flade er lidt
konkav, og saavel dens øverste som nederste Del er besat med
flere Rækker stærke Tænder, Fig. 11, a. Den forlængede
Del af Tangen er meget bred og er paa den ydre Flade
af den afrundede Ende riflet, Fig. 11.6.
De lige Pedicellarier, som hverken Sars eller Norman
har iagttaget, staa enkeltvis og langt fra hinanden langs
Ambulacralfuren, lige ved Grunden af den indre
Ambula-cralpig. Basilardelens undre Rand danner en stump
Vinkel, den øvre Rands Midtparti en liden Fremstaaenhed, og
paa hver Side af denne er en liden, rund, konkav
Ledcle-flade, Fig. 12. 13, a. Kjæverne ere langstrakte; deres
øverste, frie Ende er tilspidset og noget krumbøiet indad;
deres nederste, brede Del gaar over i en konisk
Forlængelse, paa hvis runde Ende findes en Leddeflade, der
artikulerer med Basilardelen. Deres ydre Flade er kun lidet
konvex og frembyder et netformigt Udseende med
temmelig tætte Masker, der staa i Længderækker, Fig. 12.13, 6.
Deres indre Flade er konkav og fornemmelig langs
Randene tæt besat med uregelmæssige, kortere eller længere
Tænder, Fig. 12, c.
Sars angiver i sin første Afhandling over Asterias
Mülleri (Fauna littoralis Norvegiæ, 1ste Hefte), at „de
saakaldte Furepapiller danne 2—3, noget uregelmæssige
Rækker." I hans senere Arbeide over Norges Echinodermer
siger han, at Asterias Mülleri egentlig ikke har mere end
en Række Furepapiller, den anden og tredie Række, som
han tidligere antog for Furepapiller, er ikke saadanne,
men Pigge, der tilhøre Hudskelettet.
Ifølge vore Undersøgelser har Asterias Mülleri virkelig
to Rækker Furepapiller, hvoraf den ydre Række, hvis Pigge
ere noget kortere end de i den indre Række, faar et
noget uregelmæssigt Udseende derved, a!t Papillerne staa
længere fra hverandre. Det forholder sig nemlig saaledes, at
i Regelen er hveranden Adambulacralplade forsynet med
2, hveranden med 1 Papille. Dog hænder det, at der kan
være 2—3 Adambulacralplader efter hinanden, der hver
kun bærer en Pig; men dette hører til Undtagelserne.
Asterias grønlandica, St., med hvilken man har villet
identificere Ast. Mülleri, har de samme to Former af
Pedicellarier, som ovenfor ere beskrevne og adskiller sig i
ingen Henseende fra dem. Men imedens de lige
Pedicellarier findes kun sparsomt langs Ambulacralfuren hos
Asterias Mülleri, ere de i rigelig Mængde tilstede hos Asterias
grønlandica, hvor de danne ligesom smaa Duske langs Fu-
with pedicellariæ on their external basal halves. These
cruciform pedicellariæ are rather large in proportion to
the size of the starfish. The basal portion is broad, and
the inferior margin, is much bent, with the apophyses strong,
and rather protuberant (pl. Ill, fig. 10, a). The jaws are
narrow, and somewhat blunted at the free extremity, also,
very broad, at the point where they enter upon the
elongation (fig. 10, 6). The external surface is very convex,
and on the exterior half, it is furnished with close-set
vac-uola (fig. 10, c). The internal surface is slightly concave,
and both its superior and inferior portions, are beset with
several series of strong teeth (fig. 11, a). The elongate
portion of the forceps is very broad, and striated on the
exterior surface of the rounded extremity (fig. 11,6).
^ The rectiform pedicellariæ; which have been observed
by neither Sars nor Norman; are placed singly, and at
long intervals from each other, along the ambulacra!
furrow, close to the base of the inner ambulacral spike. The
inferior margin of the basillar part forms an obtuse angle.
On the superior mesial margin, a small protuberance
occurs, and upon each lateral surface of this, there is a
small, circular, concave, articulator}- surface (figs. 12, 13, a).
The jaws are elongate, with the superior free extremity
acuminate, and somewhat curved inwards; their inferior,
broad portion, passes over into a coniform elongation, on
the round extremity of which, there occurs an articulatory
surface which articulates with the basillar portion. Their
exterior surface is only slightly convex, and presents a
reticidated appearance, with rather close meshes, arranged
in longitudinal series (fig. 12, 13, 6). Their interior surface
is concave, and, especially along the margin, is closely
beset with irregular, shorter or longer teeth (fig. 12, c).
Sars states in his first paper on Asterias mülleri (Fauna
littoralis Norvegiæ, Iste Hefte) that "the so-called
furrow-"papillæ form 2—3 somewhat irregular series". In his
later work upon Norway’s Echinodermata, he says, that
Asterias mülleri has not, really, mox-e than one series of
furrow-papillæ; the second and third series, which he
previously supposed to be furrow-papillæ, not being so; but
spines, pertaining to the dermal skeleton.
According to our researches, Asterias mülleri has really,
two series of furrow-papillæ, of which, the exterior
series, whose spines are somewhat shorter than those of the
inner series, has a somewhat irregular appearance, owing
to the papillæ being placed further apart from each other.
The fact is, that usually, the ambulacral plates are
furnished with 2, and 1, papilla alternately. It happens
however, that there can be two or three adambulacral plates,
placed one behind the other, and each of them carrying
only one spine; but this is an exceptional case.
Asterias grænlandica, St., with which it has heen
proposed to identify Asterias mülleri, has the same two forms
of pedicellariæ which have heen described previously; and
its pedicellariæ differ in no respect from these. But, whilst
the rectiform pedicellariæ are only found, sparingly, along
the ambulacral furrow in Asterias mülleri, they are
present in rich abundance in Asterias grænlandica, where, they
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