Randplade, imedens den undre, lidt konvexe Flade, bidra- 
ger i Forening med Ventralpladen til at danne et fælles 
Støttepunkt for den brede, paatversgaaende Paxillarrække, 
der er nærmest Furepapillerne. 
De ventrale Randplader, Tab. IX, Fig. 13, b, ere 
ligeledes fladtrykte; de ere noget bredere end de dorsale, 
men have ligesom disse en trekantet Form, hvis bredere 
Del vender udad og danner med sin undre Flade Støtte- 
punktet for den dorsale Randplade. Den ventrale Rand- 
plades smalere Del vender indad; dens øvre Flade er kon- 
kav og hviler for største Delen paa Adambulacralpladens 
undre, afrundede Rand, Tab. IX, Fig. 13, a (i Interbrachi- 
alrummet støder den til en Bugplade); dens undre Flade 
er lidt konvex og danner i Forening med den dorsale 
Randplades bredere Del en Slags Articulationsflade for 
den føromtalte, paatversgaaende Paxillarrække. 
Saavel de dorsale som ventrale Randplader staa paa 
Armens bredere Del og i Armvinkelen lidt fra hverandre, 
men staa tættere og tættere sammen, alt eftersom de nærme 
sig Armenden. 
Solaster papposus har ogsaa to Rækker Randplader, 
der ligeledes ere vel skjulte, men adskille sig dog fra dem 
hos endeca væsentlig derved, at de hos papposus tilsammen 
bære kun en Række Paxiller, imedens de hos endeca bære 
hver sin, altsaa to. 
De dorsale Randplader hos Sol. papposus ere tem- 
melig smaa, Tab. IX, Fig. 12, c, og ere paa den øverste 
Del af Armen aflange, imedens de midt paa og paa den 
smalere Del ere næsten terningformede. Der, hvor de 
bære en Paxille, støde to sammen, Tab. IX, Fig. 12,c, 
og danne paa deres ydre Ende en konkav Artikulations- 
flade, der optager den store Paxille, som danner Grændsen 
imellem Ryg og Bug; meget ofte støde dog en Kalktrabe- 
kels indre Ende til den nævnte Ledflade for ligesom at 
fuldkommengjøre denne, Tab. IX, Fig. 12, d, for Paxil- 
lens store Ledhoved. Imellem disse dorsale Randplader, 
der danne Artikulationsfladerne for Paxillerækken, er der 
andre dorsale Randplader, der ingen Paxiller bære, men 
kun med sin ydre Ende forene sig med det almindelige 
Kalknet. De dorsale Randplader hvile med sin indre Ende 
paa de ventrale Randplader, — stundom støtte to af de 
førstnævnte sig til en ventral Randplade. 
Paa ældre Dyr ere de dorsale Randplader, der danne 
den forbeskreyne Ledflade, fuldstændig sammenvoxet med . 
Paxillens Basaldel, og da artikulerer denne med den til- 
svarende ventrale Randplade, — fjerner man saa en af 
disse Paxiller, ser det ud, som om der ingen dorsale 
54 
superior, slightly concave, surface, upon the corresponding 
ventro-marginal plate, whilst, the inferior, slightly convex 
surface, in conjunction with the ventral plate, assists, in 
forming a joint support for the broad transverse paxillar 
series found next to the furrow-papille. Å 
The ventro-marginal plates (Pl. IX, fig. 13, b) are 
also flattened, but they are somewhat broader than the 
dorsal plates, yet, like these have a triangular shape, with 
the broad part turning outwards and forming with its infer- 
ior surface, an abutment for the dorso-marginal plates. The 
accuminate part of the ventro-marginal plates turns inwards, 
and the superior surface is concave; the greater portion 
of it, rests on the inferior rounded margin of the adam- 
bulacral plates (Pl. IX, fig. 13, a), (it unites, in the inter- 
brachial space to a ventral plate). The surface 
is slightly convex, and in conjunction with the broad part 
of the dorso-marginal plates, forms a kind of articulatory 
surface for the transverse paxillar series previously refer- 
red to. 
inferior 
Upon the broad part of the rays, and also, in the 
brachial angle, both the dorso-marginal and the ventro- 
marginal plates, are situated a little apart, but they come 
together, gradually, closer and closer, as they arrive at the 
tip of the ray. 
Solaster papposus has also two series of marginal 
plates, which are, likewise, well concealed, but yet, differ 
from those of endeca, principally, in this, that im Solaster 
papposus, they carry, jointly, only one series of paxillæ, 
whilst, in Solaster endeca, they each carry one series, to- 
gether two series of paxillæ. 
The dorso-marginal plates in Solaster papposus are 
rather small (Pl. IX, fig. 12, c), and upon the superior 
portion of the ray, they are oblong, whilst, upon the mesial 
part, and on the narrow part of the ray, they are nearly 
dice-formed. At the point where they carry a_paxilla, 
two of them unite (Pl. IX, fig. 12, c), forming on their 
exterior extremity a concave articulatory surface, which 
receives the large paxilla which forms the margin between 
the abactinal and actinal surfaces: very frequently however, 
the inner extremity of a calcareous trabeculum abuts upon 
the articulatory surface referred to, completing it, as it 
were, (Pl. IX, fig. 12, d) to receive the large articulating 
head of the paxilla. Between these dorso-marginal plates 
forming the articulatory surfaces for the paxillar series, 
there are other dorso-marginal plates which carry no pax- 
illæ, but connect to the general calcareous reticulation with 
their outer extremities only. The dorso-marginal plates 
rest, with their inner extremities upon the ventro-marginal 
plates, and occasionally, two of the first named plates, join 
themselves to one ventro-marginal plate. 
In aged specimens, the dorso-marginal plates forming 
the previously described articulatory surfaces, are completely 
grown together at the basal part of the paxillæ, and in 
this case, the paxillæ articulate wih the corresponding 
ventro-marginal plate. When we remove one of these pax- 
illæ it appears as if no dorso-marginal plates were to be 
