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40
Af disse Afvigelser af Rachis er igjen den bilaterale
Sy-nietri for en stor Del afhængig. Vi have seet. at
omendskønt den bilaterale Anordning egentlig er gjennemgaaende
hos Alle. er der dog Exemplarer, hvor den skjuler sig saa
godt. at (len ved overfladisk Betragtning let. lean oversees,
imedens den hos yngre Specimina er let ioinefaldende; og
hvad nu Polyperne angaar, saa frembyde de jo mange
Forskjelligheder ikke alene paa Exemplarerne sig imellem
men endogsaa paa selvsamme Stok. Saaledes finde vi store
og smaa i den samme Koloni, hvilke ere forskjellige i
Farve, eftersom de ere yngre eller ældre, ligesom
Tentaklernes Forhold til Polypkroppen varierer betydeligt.
Zooider findes jo paa Alle; de have samme Fonn,
der er ganske eiendommelig, idet de ere forsynede med en
lang Tentakel, der kan ganske indtrækkes i den runde,
kugle-forniige Krop. Paa enkelte Exemplarer kan Tentakelen va*ro
indtrukken hos saagodtsom alle Zooider, og de ligne da
almindelige Zooider høs Virgiäariderne; paa andre er
Tentakelen enten ganske eller mer® eller mindre udstrakt, og
da se de ud som lange nedhængende Papiller, Tab. VIII,
Fig. 29. Det er sandsynligvis disse Lindahl ogsaa luir
bemærket, og som han har kaldet "skaftet", uden nærmere
at beskrive dem. Men ihvorvel Zooiderne ere ens hos
Alle — paa meget unge Exemplarer er Tentakelen kun lidet
udviklet — saa staa de dog snart tæt sammen, snart mere
spredte paa de forskjellige Specimina. Endelig er Farven
ogsaa temmelig variabel, især gjælder dette Polyperne; den
brune Farve er dog Grundtonen.
Dr. Lindahls to Exemplarer have, efter Alt at dømme,
været meget unge; herpaa tyder Polypernes Antal og
Stør-relse, men hovedsagelig den Omstændighed, at han ingen
Generationsorganer fandt hos dem. Vi have to Exemplarer
af omtrent samme Storrelse som Lindahls, nemlig No. 5
og (i; men hos disse, ligesom hos de 4 mindre.’fandt vi
heller ikke Kjonsorganer. imedens hos alle de øvrige, der
havde en høiere Alder, fandtes Generationsorganer vel
udviklede, dog saaledes, at hos enkelte (No. 7) havde kun
de ydre Polyprækker fuldt udviklede Kjonsorganer; alle de
øvrige Polyper hos dette Exemplar vare endnu kjønsløse.
Men hos de fuldt ud voxne havde samtlige Polyper
udviklede Generationsorganer. Paa Eliis’s Exemplar have
Kjons-organerne visselig været udviklede; han omtaler idetmindste
nogle runde Legemer, som kan antages for Æg.
Omendskjont baade Eliis’s og Mylius’s Beskrivelser
ere meget ufuldstændige og kunde heller ikke være andet,
saasom enhver af dem kun havde et torret Exemplar til
deres Disposition, saa kan der dog ikke reises Skygge af
Tvivl om. at vore Exemplarer ere identiske med deres, og
at saaledes Ellis’s "Chtsta’polype" og Mylius’s
„Aeuegrön-ttindischc Thicrpldanze" ei’ gjenfunden, og det i saamange
vel konserverede Exemplarer, at de ikke paany skulle gaa
tabte for Videnskaben.
actual terminal point. On these divergencis in the rachis,
the bilateral symmetry, again, is. in a great degree
dependent. We have seen, that although the bilateral
arrangement, really, is present them all, vet, there are specimens
where it is so concealed, that on superficial examination,
it may easily be overlooked, whilst, in the younger
specimens it. prominently, meets the eye. In respect to the
polyps; these too, also, present many divergencies, not only
between the specimens themselves, but even in the polyps
of one and the same stalk. For instance, we find large
and small ill the same colony, which very in colour,
according as they are younger or older, whilst, also, the
proportion between the tentacles and the body of the polyp
differs greatly.
Zooids are, however, found on them all, and these
have the same quite peculiar form, inasmuch as. that they
are furnished with a. long tentacle, with is capable of being
retracted into the circular bullet-shaped body. In some
specimens, the tentacle can be retracted in nearly the whole
of the zooids, and they, then, resemble the common zooids
in Virgidaridæ. In other specimens, the tentacle is, entirely,
or more or less, partially, extended, and they then resemble
long pendant papillæ (Pl. VIII, fig. 29). It is.
presumably, these, that Lindahl has also observed, and which
he has called "skaftet", without, however, more minutely,
describing them. But. although, the zooids are alike in
all. yet, the tentacle is, in young specimens, only little
developed ; and further, they are situated, oftentimes, compactly,
oftentimes more dispersed, in the different specimens.
Finally, the colour is, also, rather variable, and this is
specially so. regarding the polyps. Brown colour is.
however, the prevailing tone.
T)r. Lindahl’s two specimens have, to all appearance,
been very young; the number and size of the polyps point
to that; but, mainly, the circumstance, that lie did not
observe generative organs in them, leads to that conclusion.
We have two specimens of about similar size as Lindahl’s
viz. No. 5 and (i. but, in these, as well as in the 4
smaller ones, neither have we observed sexual organs; whilst,
in all the others which had a more advanced age,
generative organs, well developed, were observed; but vet, in
individuals (No. 7) the outer series of polyps, alone, had
fully developed sexual organs. All the other polyps in
this specimen, were, as vet, sexless; but, in the full grown
individuals, the whole of the polyps had developed
generative organs. In Ellis’s specimen, the sexual organs have
evidently been developed; at all events, lie speaks of some
round bodies, which he assumes to be ova.
Although both Ellis’s and Mylius’s descriptions are
very incomplete, and could not well be otherwise, seeing,
that each of them, had at their disposal, only, one dried
specimen; yet, there can not be raised the shadow of a
doubt, that our specimens are identical with theirs; and.
that therefore. Ellis’s " Clusterpolypc", and Mylius’s "Neue
gröriländisc/ie 21iierphlanzeil, are now rediscovered, and
in so many well preserved specimens, that they are not
likely, again, to become lost to science.
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