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50
Vi omtalte, at paa Svælgets vdre Flade fæster de 8
Septa sig. Disse, der udgaa fra den indre Kropsvajg og
insererer sig paa Svælget, deler den øverste Del af
Ga-stralhulheden i 8 Kamre, De to dorsale Septa, Fig. 43, /,
konvergere stærkt henimod Svælget, saa at det dorsale
Kaminer, Fig. 43. g, her bliver temmelig trangt; de ventrale
Septa, Fig. 43, h, konvergere* ikke saameget, derfor er ogsaa
Bugkammeret videre, Fig. 43, /, men Sidekamrene ere videst,
Fig. 43, /.". Disse Septa, der ere Forlængelser af
Krops-væggens indre Bindevæv, dannes af en Bindevævsmeinbran,
Fig. 43, 1. 50, <t. hvori tindes mange tine, forgrenede
Ernæ-ringskanaler med sit Epithel. Fra denne hyaline
Binde-va’vslamels ene Flade udgaa listeforniige Forlængelser, Fig.
50, h, paa hvis begge Sider Længdemusklerne ere fæstede,
Fig. 50, c\ udenpaa dette Muskellag or et Epithel, dannet
af lignende Celler som de, detr bokla’dc Svælgets ydre Flade,
og som tidligere er omtalt, Fig. 50, e. Paa
Bindevævsla-mellens anden Flade sees Tvcrniusklerne. Fig. 50, d. eier
ligeledes ere overtrukne med fuldkommen lignende Epithel,
som altsaa tapetserer hele Kammeret,
Muskelanordningen paa Septa er, som man har seet,
noget forskjellig fra den. eier finder Sted hos Pcnncdid iderne
i Almindelighed; thi, saavidt os bekjendt, er der ikke
tidligere iagttaget de listeforniige Fremspring paa hvert
Sep-tunis ene Flade, til hvilke Lrengdemusklerne ere fæstede.
Disse Fremspring ere saa store, at de endog med en svag
Loupe kunne sees; men forovrigt er Anordningen den
sædvanlige, nemlig at de transversello Muskler paa den ene
Side vender mod Polypens Dorsalflade, og de longitudinelle
Muskler paa den anden Side mod VentralHaden, saaledes
at Dorsalkammerets Sidevægge, Fig. 43, g, kun har
trans-versclle Muskler, imedens Ventralkammeret derimod har
alene longitudinelle Muskler, Fig. 43, i.
Fra den nederste Ende af Svælget blive Septa, naar
de forlade dette, betydelig smalere* og gaa nu langs hele
Væggen af Mavehulheden, Fig. 47, b, under Navn af
Septula lige ned til dennes Bund, Fig. 47, c. Septula danne
altsaa paa • Mavevæggen 8 stærke, listeforniige Fremspring
med en fri Hand.
Paa hver Side af Septulum er ligesom paa Septum
Muskellaget fæstet, paa. elen ene Side nemlig
Længdeniusk-lerne, Fig. 49, a, paa den anden Tveriuusklerne, Fig. 49’, a,
og til den fri Rand er Gastralfilanientet bundet meel en
meget tynel Bindeva’vsmombran, Fig. 49, b.
Den nederste frie, runde Rand af Svadget er tyk,
ligesom opsvulmet, og her samler ele circulære Muskler sig
Between the folds of the gullet, the remains of niulluscous,
crustaceous, and echinodermatous larva; were observed,
also, a great many diatomés, and all these nutritive
substances were well enclosed in a rich mucous secretion.
We stated that, the 8 septa are attached to the
exterior surface of the gullet. They issue from the inner
Avail of the body, inserting themselves in the gullet, and
divide the superior part of the gastric cavity into t-i
chambers. The two dorsal septa (tig. 43, /). converge, greatly,
towards the gullet, so that, the dorsal chamber (tig. 43)
becomes rather narrow, hero. The ventral septa (Hg. 43, A),
do not converge so much, and the ventral chamber is
therefore also wider (Hg. 43, i), but the lateral chambers are the
widest (fig. 43, If). These septa, which are prolongations of
the inner connective-tissue of the wall of the body, are formed
by a membrane of connective-tissue (figs. 43,1, 50, a), in which,
is found, many minute nutrient eluctiferous ramifications with
their epithelium. From the one surface of this hyaloid
connective-tissue lamella, fillet-formed prolongations issue (tig. 50, b)
to both of whose sides longitudinal muscles are adherent.
Oil the exterior of this muscular layer, there is an
epithelium, formed of similar cells to those which cover the
exterior surface of the gullet, and which have previously
been spoken of (fig. 50, e). On the other surface of the
connective tissue lamella., transverse muscles are seen (fig.
50, d), which, also, are clothed with exactly similar
epithelium; and this, consequently, coats the entire chamber.
The muscular arrangement of the septa is, as will
be seen, somewhat different from that which is found
in Pennatululat • in general; because, so far as we are
aware, there has not, previously, been observed, the
fillet-formed prominence, em the one surface of each septum, to
which the longitudinal muscles are attached; These
prominences are se> large, that they may, even, be observed
with an ordinary magnifying glass; but, the arrangement,
otherwise, is the usual one, viz. that the transversal muscles
of the one side, face towards the polyps dorsal surface;
and the longitudinal muscles of the other side, face towards
the ventral surface, so that, the lateral walls of the
dorsal chamber (fig. 43, g) have only transversal muscles;
whilst, on tin* other hand, the ventral chamber has only
longitudinal muscles (fig. 43. f).
From the lower extremity of the gullet, at the- point
where they leave it, the septa become considerably
narrower, and then pass along the entire wall of the ventral
cavity (fig. 47, b), appearing as septula, and extending right
down to the bottom (fig. 47, c). The septula form, thus,
on the wall of the stomach, 8 strong fillet-fornied
prominences having a free margin.
On each side of the septulum; as in the case of the
septu$j|| the muscular layer is so attached, that on the
one side we find longitudinal muscles (Hg. 49. a), and
on the other siele, transverse muscles (fig. 491, «), and
the gastral filament is secured to the free margin, by a
very thin membrane of connective-tissue’ (fig. 49. b).
The inféribr, free, round margin of the gullet, is thick,
as if it were tumifieel, and in this situation, the circular
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