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hverken paa det levende Dyr eller det i Spiritus
opbevarede kan iagttage Kalkplader paa Bugens ydre Plade.
2 Rækker cylindriske Fødder med Sugeskive og uden
Spikier, Tab. XI, Fig. 2, b. 4, c. Ingen Pedicellarier.
Ryghudens indre Flade viser sig ved Indtørring at
være ligesom overstrøet med yderst fine, ved blotte Øie neppe
synbare Kalkkorn, der ikke rage langt ind i Huden og
ikke staa i nogensomhelst Forbindelse med Ryggens
Kalkpigge. Ved meget stærk Forstørrelse vise disse Kalkkorn
en afrundet, punkteret Overflade, Tab. XI, Fig. 5.
Henimod Søstjernens Rand, hvor Ryggen gaar over
i Bugen, findes paa den indre Flade en bueformig Række
af smaa, flade, uregelmæssige Kalkplader, der staa langt
fra hverandre, rage kun lidet ind i Hudens Tykkelse og
bære ingen Pigge, Tab. XI, Fig. 6, e. Disse Plader
kunne vel betragtes som rudimentære dorsale Randplader.
Noget Skelet findes ikke i Ryghuden; men de fine
Kalkkorn, ligesom de nylig beskrevne Plader, ere svage
Antydninger til et saadant.
Paa den indre Bugflade sees lignende Kalkkorn; men
foruden dem er der ogsaa et virkeligt Hudskelet.
Hudskelettet paa Bugfladen dannes af 3 bueformige
Rækker flade, temmelig regelmæssigt formede Kalkplader,
Tab. XI, Fig. 6. Disse ere paa den indre Flade
ophøi-ede paa Midten og ved stærkt Bindevæv forenede med
hverandre, hvorved hele Rækken faar Udseende af en
Ro-senkrands.
Den yderste Række, Tab. XI, Fig. 6, /, er den
længste, og idet den kommer hen til Armens Rand, støde
Pladerne til Adambulacralpladerne uden at forene sig med
disse. Paa enhver Plades ydre Flade er der 3 temmelig
tykke Pigge, der som oftest staa i Trekant, Tab. XI, Fig.
4, a. Det er denne Række, som danner de ventrale
Randplader med sine Pigge.
Den anden Række Plader bestaar paa Midten af 2
—3 adskilte Rader, Tab. XI, Fig. 6, g, men bliver til en
enkelt, idet de nærme sig Armens Rand. Enhver af disse
Plader bære en eller to Pigge.
Den tredie, inderste Række, Tab. XI, Fig. 6, h, er
som den første enkelt, temmelig kort, og hver Plade bærer
en Pig. Imellem disse Pladerækker sees spredte Plader,
der dels bære en Pig, dels ere uden saadan.
Ambulacx-alpladerne have brede, bladformige
Forlængelser,Tab. XI, Fig. 6, a.
Adambulacralpladerne, Tab. XI, Fig. 6, b, ere
næsten firkantede, have et Indsnit paa den indre Flade, der
optager Ambulacralpladens ydre, afrundede Proces, og paa
deres underste Flade findes 3 divergerende Pigge, hvoraf
den, der vender ind mod Ambulacralfuren, er den længste.
specimens preserved in spirit, is it possible, to observe the
calcareous plates of the exterior actinal surface.
There are 2 rows of cylindrical suckers with
sucker-disks, and free from spiculæ (Pl. XI, fig. 2, b. 4, c). There
are no pedicellariæ.
When dried, the inner surface of the integument of
the abactinal surface, appears as if it was sprinkled with
extremely minute calcareous grains, barely visible to the
naked eye, and which do not sit deeply in the integument.
These have no connection whatever with the calcareous
spines of the abactinal surface. On being powerfully
magnified, these calcareous grains present a rounded
punctuated surface (Pl. XI, fig. 5).
Towards the margin of the starfish; where the
abactinal and actinal surfaces meet; there occurs on the inner
surface, an arcuate series of small, flat, irregular calcareous
plates, situated considerably apart from each other, and
only slightly, protruding into the body of the integument,
and these plates carry no spines (Pl. XI, fig. 6, e)
The plates referred to, may, presumably, be considered
to be rudimentary dorso-marginal plates.
No skeleton is found in the dorsal integument; but
the minute calcareous grains, and the plates just lately
described; are faint indications of a skeleton.
On the inner actinal surface, similar calcareous grains
are seen; but besides these, a real integumental skeleton is
also observed.
The integumental skeleton of the actinal surface, is
formed by 3 arcuate series of flat, rather regularly formed
calcareous plates (Pl. XI, flg. 6). Their inner surfaces
are elevated in the middle, and are united to each other by
strong connective tissue, giving to the entire series the
appearance of a rosary.
The exterior series (Pl. XI, fig. 6, f), is the longest,
and as it approaches to the margin of the ray, the plates
abut upon the adambulacral plates, without, however,
uniting to these. On the exterior surface of each plate, there
are 3 pretty thick spines, most frequently placed
triangularly (Pl. XI, fig. 4, a). It is this series which forms the
ventro-marginal plates, with their spines.
The second series of plates consists, in the mesial
part; of two series of 2—3 separated rows (Pl. XI, fig.
6, g) which, as they approach" the margin of the ray,
become one. Each of these plates carries one or two spines.
The third or imost series (Pl. XI, fig. 6, h) is, like
the first series, single, rather short, and each of its plates
carries one spine. Scattered plates are also visible
between these series of plates, carrying sometimes, one spine,
and sometimes without any spine.
The ambulacral plates have broad leaf-formed
prolongations (Pl. XI, fig. 6, a).
The adambulacral plates (Pl. XI, fig. 6, b) are
almost square, and on the inner surface, have a groove that
includes the ambulacral plates exterior rounded process.
Upon their inferior surface, 3 diverging spines are seen, of
which, the one that turns inwards towards the ambulacral
fuiTOw is the longest.
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