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dens øverste er næsten lige og paa Midten forsynet med en
pyramideformig Kam (crista), Fig. 6, a, der seet en face
ligner en liden Tap, Fig. 5, a; paa hver Side af denne
Kam sees en liden Grube, Fig. 6, b, som tjener til
Insertion for Muskler.
Kjæverne ere langstrakte og smale, paa hele deres ydre
Flade gjennembrudte og have ned imod deres Grunddel
indad et halvmaaneformigt Indsnit, Fig. 5, b. 6, c, ligesom
deres indre Rande ere fint sagtakkede, Fig. 6, d.
Den anden Form af de lige Pedicellarier, som alene
findes paa Skiven, have en særegen Form og ere meget
mindre end de øvrige. Basaldelen danner en Pyramide
med en bred, lige Grunddel og stærkt skraanende
Sideflader, der afgive Leddeflader for Kjæverne, Fig. 7, a. Disse
ere krumbøiede, bredere foroven, hvor der fra den
afrundede Ende fremrager mange Kalkspidse, der ere stillede
saaledes, at de fra den ene Kjæve gribe ind i den anden
Kjæves Kalkspidser. Det er kun den øverste Halvdel af
Kjæverne, der støder mod hinanden; paa den nederste
Halvdel rager enkelte Kalkspidser frem, men her mødes
ikke Randene, tvertimod er der et stort aabent Rum, naar
Kjæverne ere sluttede, Fig. 7, b. Saavel Kjæverne som
Basaldelen er tæt gjennembrudt, og da Aabningerne paa,
Kjæverne ere temmelig regelmæssigt stillede, fremkommer
derved et gitret Udseende, Fig. 7, b.
Bugfuren er, som almindelig hos Slægten Asterias,
optaget af 4 Rækker Fødder, og langs dens Rande sees i
Regelen 3 Rækker temmelig lange, noget fladtrykte
Papiller, hvoraf de, der staa inderst og rage ind i Furen, ere
de korteste; de i den yderste Række ere længst. Paa store,
gamle Individer er der flere Furepapiller, af hvilke kun de,
der staa inderst, danne en regelmæssig Række; de øvrige
staa temmelig uregelmæssigt og danne tildels smaa
Grupper paa 4—5, der udgaa fra hver Adambulacralplade. Ved
Grunden af de inderste Furepapiller sees isolerede, langt
fra hinanden staaende, lige Pedicellarier, der sidde paa en
lang Stilk. Disse Pedicellarier findes væsentligst paa den
midterste Del af Ambulacralfuren. Lidt udenfor den ydre
Række Furepapiller sees to Rækker Pigge, som ere meget
lange, noget fladtrykte, staa temmelig regelmæssige, Fig. 2,
og som aftage betydeligt i Størrelse mod Armspidsen. Paa
store Exemplarer føier der sig ofte flere Pigge til disse
Rækker, hvorved de blive mere uregelmæssige.
Ryggens Hudskelet bestaar af smaa, smale, aflange
Kalkstykker, som, idet de lægge sig paa hverandre, danne
kortere eller længere Kalkbjelker, der forbindes med hin-»
anden og danner derved et meget aabent Net med store
Masker, hvori sees mange Tentakelporer, Fig. 8, a. Dette
Kalknet ophører paa Armenes yderste Fjerdedel, hvor der
kun findes spredte Kalkkorn i Huden.
Paa Skiven er et uregelmæssigt formet Centralstykke,
Fig. 8, b, hvortil støder straaleformigt 5 aflange Kalkstyk-
tion is small, with a very convex inferior margin. The
superior margin is almost straight, and in its mesial part, is
furnished with a pyramidal ridge, (crista) (fig. 6,a) which, viewed
from the front, resembles a small, conical protuberance (fig.
5, a). On each lateral surface of this ridge, there occurs a
small cavity, (fig. 6, b) serving for muscular insertions.
The jaws are elongate and narrow, and have the
entire exterior surface perforated; towards the internal basal
part, they have a crescent shaped cavity, (fig. 5, b, 6 c) whilst,
also, the interior margin is minutely serrated (fig. 6, d).
The other form of rectiform pedicellariæ is only found
upon the disk; it is peculiar in form, and much smaller
than the others. The basal part forms a pyramid, having
a broad straight base, with strongly sloping lateral surfaces,
which furnish articulatory surfaces for the jaws (fig. 7, a).
These are bent; broadest superiorly, where there projects
from the rounded extremity, numerous calcareous points, so
situated, that those of one jaw interlace with those of the
opposite jaw. It is only the superior half of the jaws which
close together on each other. On the inferior half, a few
calcareous points project, but in this situation, the margins
do not close on each other; on the contrary, a large open
interspace remains when the jaws are closed (fig. 7, b).
Both, the jaws and their basal region, are closely
perforated, and, as the perforations of the jaws are rather
regularly placed, a grated appearance is produced (fig 7, b).
The ventral furrow, as is the case, generally, in the
genus Asterias, is occupied by 4 series of suckers, and
along its margins, there is, as a rule, visible, 3 series of
rather long, somewhat flattened papillæ, of which, those,
situated innermost and projecting into the furrow are the
shortest: those in the outermost series are the longest. In
large aged specimens, the furrow papillæ are more numerous,
whilst, only those situated innermost, form a regular series;
the others are placed, partly irregularly, and form, partly,
small groups of 4—5 springing from each adarabulacral plate.
At the base of the innermost furrow-papillæ, isolated
rectiform pedicellariæ are seen, seated on long peduncles, and
situated at long intervals from each other. These
pedicellariæ, are principally found on the mesial portion of the
am-bulacral furrow. Slightly beyond the exterior series of
fur-row-papillæ, 2 series of spines are seen; these are very long,
somewhat flattened, and rather regularly placed (fig. 2);
towards the brachial extremity, the size diminishes
considerably. In large specimens, several spines often unite to
these series, producing in them, still greater irregularity.
The abactinal dermal skeleton consists, of small,
narrow, oblong calcareous ossicles, which, by disposing them
selves upon each other, form shorter or longer, calcareous
rods, united together, and thus form a very open
reticulation, with large meshes, in which many tentacular pores
appear, (fig. 8, a). This calcareous reticulation ceases on
the distal brachial quarter-length, in which situation, only
scattered calcareous grains are found in the integument.
On the disk, there is found an irregular shaped mesial
ossicle, (fig. 8, b) upon which 5 oblong calcareoüs ossicles
3*
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