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langt, som G-astralfilamenterne naa, nemlig indtil 20""" ned
i Rachis, der udgjør egentlig Bunden af Polypens
Mave-hulhed. Alle 8 Gasträiülamenter ere optagne af
Kjønsør-ganorne; men paa de to dorsale begynde de et længere
Stykke nede end paa de øvrige 6. De ere i saadan
Rigdom tilstede, at de hos mange Polyper ganske udfylde
Grastralhulheden. Denne bliver ned imod Bunden alt
smalere og smalere og ender i en trang Kanal, der gaar over
i det transverselle Kanalsystem.
Paa enhver Polypstok ere samtlige Polyper af samme
Kjon; af de 6 Exemplarer, hvor Kjønsorganerne vare
udviklede, var der 4 Hunner og 2 Hanner. Disse sidste
havde intet Særpræg, ifolge hvilket man af det Ydre
skulde være istand til at skjelne dem fra Hunnerne; men
naar man undersøgte (•ienerationsorganenie. saa vare disse
hos Hannen melkelivide, imedens de lvos Hunnen havde en
rodlig Farve.
Vi have i vor Beskrivelse af Umbéllulciens Ydre
omtalt løseligt de ganske eiendommelige Zooider, som findes
overalt paa Stokken, naar undtages den nederste Did af
det bulbøse Parti; vi skulle nu gaa noget nærmere ind
paa dem.
Den noget aflange Zooidekrop med den lange Tentakel,
Fig. 56, a, er udvendigt beklædt med et Epithellag, der paa
Kroppen er temmelig tykt, bestaaende af flere Lag Celler,
imedens det paa. Tentakelen og dens Pinnuler er noget
tyndere, ligesom Cellelagene her ere fjerre. Cellerne ere
polyædriskc og fuldkommen lig dem, som findes paa
Stok-coenenchymets ydre Flade, Fig. 57, a. 58, a. 59, a. 60.
Imellem Ectodermcelleriie og nedsænket i dem sees en
Mamgde af de encellede Slim kjertier med deres Kjerne og
lUlfbrselsgang, Fig. 57, b. 58. 59. 60, b. Paa et Tversnit
vise disse Kjertler sig som en smuk, lysende Perlekrands,
Fig. 58. 60; men seet fra Overfladen vise de sig som store
Fordybninger i Epithellaget, Fig. 59, ligesom de uden at
være præparerede med Jodgrønt synes at være ganske
tomme. Selv efter Farvningen synes mange af dem at
være k jerneløse, og det har forekommet os, at mange ogsaa
vare aldeles uden Indhold. Indenfor Ectodermet er et
smalt, hyalint Bindevæv, Fig. 58, c. 60, c, i hvilket sees fine
Ernæringskanaler, og hvortil Muskellaget, der bestaar af
sparsomme, circulære Muskelfibre, fæster sig. Fig. 58, d. og
meget stærke Længdemuskler, Fig. 58, e. 60, d.
Muskellaget er forsynet med Epitholovertræk, dannet af flere Lag
runde Celler, ganske lig dem, som tidligere ere beskrevne
paa Polypkroppcns indre Væg, Fig. 58, /. Fra
Zooide-kroppens indre Flade udgaa 8 Septa, der fæste sig paa
Svælget, Fig. 60, e, og danne derved de for Zooiden som
for Polypen almindelige 8 Kamre. Septa dannes ligesom
hos Polypen af en Bindevævslainel, paa hvis ene Side
ere transverselle Muskler, Fig. 60, f. og paa den anden
longitudinelle, Fig. 60, </; disse Muskler ere beklædte
med lignende Epithel som det, der beklæder Polypens indre
Kropsvæg. Anordningen af Musklerne er den samme som
tidligere omtalt hos Polypen. Kos Zooiden er der ogsaa
en lateral, symetrisk Retning saaledes, at i Dorsalkammeret,
which extend themselves as far as the gastral filaments
reach, or, about 20""" down the rachis ; which forms, really,
the bottom of the polyp’s ventral cavity. All of the
8 gastral filaments are occupied by sexual organs, but.
upon the 2 dorsal ones, they begin a little lower down
than on the other 6. They are present in such abundance,
that in many polyps they quite fill up the gastral cavity.
This becomes narrower and narrower towards the bottom,
and terminates in a narrow canal which passes over into
the transversal ductiferous system.
On each polyp stalk, all it’s polyps are ol’ the same
sex. In the 6 specimens in which the sexual organs were
developed, 4 were females, and 2 were males. The latter
had no distinguishing feature which enabled them by their
exterior appearance, to be distinguished from the females,
but, when the generative organs were examined, these were
found to be milk white in the males, whilst, in the females,
they had a reddish colour.
In our description of the Uinbelhda’s exterior, we
have loosely referred to the quite peculiar zooids which
are, everywhere, found on the stalk, with exception ol’ the
inferior part of the bulbous portion, and we shall now
refer to them more particularly.
The somewhat obloug zooidal body, with the long
tentacle (fig. 56, a), is, exteriorly, covered with a layer ol’
epithelium, which is rather thick upon the body, and
consists of several cellular layers; whilst, in the tentacle and
it’s piuuulæ, it is somewhat thinner, whilst, also, the cellular
layers are here, less numerous. The cells Jare polyhedrons,
and. exactly, like those found on the outer surface ol’ the
sarcosoma. of the stalk (figs. 57. a, 58. a. 59, a. 60).
Between the ectoderm cells, and depressed in them, a
multitude of the single-celled mucous glands, with their nuclei
and excretory ducts are seen (figs. 57, b. 58. 551. 60. h).
A sectional aspect shows these glands, like a beautiful,
brilliant, pearl wreath (figs. 58, 601; but, viewed from the
surface, they appear, as large depressions in the
epithelium layer (flg. 59), whilst also, until treated with Iodine
green they appear to be quite, empty. Even, after being
coloured, many of them appear to be without nucleus, and
it has appeared to us, that many of them have, really, been
without contents. Inside of the ectoderm, there is a
narrow, hyaloid connective-tissue (tigs. 58, c, 60, e) in which,
minute nutrient ducts are seen, and to which the muscular
layer is attached. This layer consists, of sparse, circular,
muscular fibres (fig. 58, d) and very strong longitudinal
muscles (figs. 58, e, 60, d). The muscular layer is
furnished with epithelium covering, formed of several layers of
round cells quite similar to those which have been
previously described as pertaining to the inner wall of the body of
the polyps (fig. 58,/). From the inner surface of the body
of the zooids, 8 septa issue; these attach themselves to the
gullet (fig. 60, e), and form, thus, for the zooid as well as
for the polyp, the 8 usual chambers. Septa are formed,
as in the case of the polyp, by a connective-tissue lamella,
on one of whose sides there are transversal muscles (fig.
60, /’) whilst, on the other side, there are longitudinal muscles
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