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15
den, smalner efterhaanden mod den spidse Ende. Den lille
Radius forholder sig til den store som 1: 9, Fig. 1.
Skivens Ryg er forsynet med endel spredte, lidt
afstumpede Pigge, luen overalt tæt besat med ligeformede
Pedicellarier. Madreporpladen næsten rund, ikke synderlig
eleveret, 8—10mm fjernet fra Arm vinkelen, Fig. 1.
Armenes Ryg have paa Midten en uregelmæssig
Længderække Pigge, der ere noget større, end de paa Skiven; paa
Siderne sees spredte, uregelmæssig stillede mindre Pigge,
der paa enkelte Stykker stille sig i Række. Paa tørrede
Exemplarer er det næsten umuligt at finde nogen
Regelmæssighed i disse Pigges Stilling. Armenes Rygflade
be-grændses af en Række korte, men stærke Pigge, Fig. 1.
Hele Rygfladen er bedækket af tætstaaende,
ligeformede, yderst kox-tstilkede Pedicellarier, hvorimellem sees
lange Tentakelrør; men paa 2 Exemplarer saaes paa en
Ann endel korsformede Pedicellarier ved Grunden af
enkelte Pigge af den midterste Pigrække, imedens der paa
de øvrige, ligesom paa et amerikansk Exemplar, kun findes
ligeformede, saaledes som af Perrier er angivet. Han har
nemlig paa de 5 i Spiritus opbevarede Exemplarer i
Parisermuseet ikke fundet korsformige Pedicellarier paa
Ryggen, uagtet han har været meget opmærksom herpaa; han
udtrykker sig saaledes: „Il est ä rémarquer que les épines
du dos ne sont pas entourées de ce cercle de pédicellaires
croisés que nous avons rencontrées jusqu’ici Jd’une maniére
constante." Regelen synes altsaa at være, at der ingen
korsformede Pedicellarier findes paa Rygfladen af Asterias
stéllionura.
Den nysbeskrevne Række Pigge, der begrændse
Rygfladen og egentlig ere dorsale Randpigge, ere derimod
omgivne af en Krands tætstaaende, korsformige Pedicellarier,
Fig. 1, 2.
Bugen er flad, og dens Fure temmelig trang, forsynet
med 2 Rækker Ambulacralpapiller, hvoraf den inderste,
nærmest Furen, har de længste og fleste Pigge, imedens
Piggene i den ydre Række ere mindre og færre i Antal og
staa ikke ganske regelmæssigt. Det forholder sig nemlig
saaledes, at som oftest bærer hver anden
Adambulacral-plade kun 1 Pig, hver anden 2.
Henimod Armens Rand er en regelmæssig Række
lange, stærke, konisk tilspidsede Pigge, der staa saa langt
fra hverandre, at snart 3—4, snart 5 Furepapiller svare
til Rummet imellem 2 Pigge. Disse lange Pigge (ventrale
Randpigge), 37 i Antal, ere paa deres ydre Side omgivne
af en Hob korsformede Pedicellarier, Fig. 2, a.
Feltet imellem Furepapillerne og de stærke ventrale
are 18mm broad at the origin, and measure from 110 to
120mm in length, and taper uniformly towards the
extremity. The disk-radius bears to the brachial radius, the
proportion of, as 1:9, (fig. 1).
The abactinal surface of the disk, is supplied with a
number of scattered, somewhat blunted spines, and, is
everywhere, closely beset with rectiform pedicellariæ. The
mad-reporite is almost circular, not much elevated, and is
situated 1—18mm distant from the interbrachial angle, (fig. 1).
The abactinal surface of the rays has a mesial
longitudinal irregularly disposed series of spines, somewhat larger
than those visible upon the disk. On the lateral
surfaces of the rays, irregularly placed, scattered spinelets are
visible, which, in some .parts, become disposed in rows. In
dried specimens, it is scarcely possible to detect any regularity
in the disposition of the spines. The abactinal surface of the
rays is bordered, by a series of short strong spines, (fig. 1).
The entire abactinal surface is covered, with close-set,
rectiform pedicellariæ, with extremely short peduncules,
between which, long tentacular tubes appear; but, upon two
specimens, however, there was remarked upon one of the
rays, a few cruciform pedicellariæ, situated at the base of
individual spines belonging to the mesial spinous series,
whilst upon the others, just, as is also the case in an
American specimen, rectiform pedicellariæ only were
observable; as has been noticed by Perrier. He has not
discovered cruciform pedicellariæ on the abactinal surface
of the 5 specimens preserved in spirit in the Paris
Museum, although he has directed much attention to this. He
„expresses himself thus: „II est a rémarquer que les
„épines du dos ne sont pas entourées de ce cercle de
pédicellaires croisés, que nous avons rencontrées jusqu’ici d’une
„maniére constante." — The rule seems therefore to be,
that no cruciform pedicellariæ are found on the abactinal
surface of Asterias stéllionura.
The spinous series above described, which border the
abactinal surface, and really form the dorso-marginal spines,
are on the other.hand, environed by a wreath, of closely
disposed, cruciform pedicellariæ (fig. 1, 2).
The actinal surface is flat; the furrow rather narrow,
and furnished with 2 series of ambulacral papillae, of which
the inner one, next the furrow, has the longest and
greatest number of spines, whilst, the spines of the outer
series are smaller and not so numerous, neither are they
quite regularly disposed. It happens, thus, that most
frequently, every second adambulacral plate carries only 1
spine, whilst, the other alternate one carries 2 spines.
In proximity to the margin of the rays, there is a
series, of long, strong, coniform spines, regularly disposed at
such interval from each other, that sometimes 3—4,
sometimes 5, furrow-papillæ, correspond to the interspace of 2
spines. The long spines are 37 in number,
(ventro-marg-inal spines) and are environed on their external margin,
by a cluster of cruciform pedicellariæ (fig. 2, a).
The area between the furrow papillae and the strong
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