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26
Man vil af ovennævnte Beskrivelse se, at Tarmrøret
vel danner Slyngninger, men ikke, som hos Bonéllia viridis
(efter Lacaze-Duthiers), danner nogen Spiral omkring den
lange Æggebeholder (matrix, la poche génitale).
Hele Mundhulheden var udfyldt af sandholdigt Ler,
hvori fandtes forskjellige Foraminiferer, Diatomeer, Alger
og Ascarider. Svælget var tomt; men strax bagenfor dette
havde det sandholdige Indhold for endel formet sig til
cylindriske, langstrakte Boli med afrundede Ender, 3—4mm
lange og 1.5—2mm tykke, og jo længere bag i Tarmen,
desto hyppigere bleve disse, saa at hele den Del, der
strækker sig fra 5te Tverslynge og til Anus, var ganske opfyldt
af disse Excrementer.
De to buskede Organer ere næsten kugledannede,
3—4mm store, og ere fæstede et paa hver Side af Rectum,
strax foran Kloakaabningen, Fig. 8, a, a. De have en
cylindrisk Stamme, der danner et Rør, som ved Udspringet
er nøgent i en Længde af omtrent lmm, Fig. 8, b; men
fra den øvrige Del af Stammen udgaar en Mængde
rør-formige Grene, Fig. 9, a, hvorfra udspringer en stor
Mangfoldighed af lange, smale, slangeformige Rør, Fig. 9, b, b.
Disse have paa deres frie Ende en tragtformig Aabning,
. som fører ind til Rørets Hulhed, og hvis Rand er forsynet
med lange Cilier, Fig. 9, c, c, 10.
I histologisk Henseende dannes de nævnte Organer
væsentligst af de samme Elementer, som Tarm- eller
Kloakvæggen, hvoraf de egentlig kunne betragtes som en
Ud-stylpning. Den indre Flade er tapetseret af et rigt
flimrende Epithel, der rager ind i Hulheden, og hvis Celler
ere store, dels runde, dels mere eller mindre aflange; de
have en temmelig stor Kjerne og et yderst finkornet
brungrønt Pigment, der ofte er saa tæt og tykt, at det ganske
skjuler Kjernen, Fig. 12, a, a; 13, b, b. Epithelet er fæ.
stet til et fibrillært Bindevævslag, hvortil Muskelhuden
støder, hvilken bestaar af Længde- og Ringfibre, som beklædes
af det flimrende Peritoneum, som altsaa danner den ydre
til Kropshulheden vendende Flade. Indeni Rørenes Lumen
iagttoges en hel Del smaa fritliggende runde Legemer, der
vare noget sammenskrumpede, forsynede enten med Kjerne
eller nogle faa Moleculer, Fig. 13, c, og som lignede de
Legemer, Kropsvædsken indeholdt, hvilke tildels vare
koagulerede i Klumper. Hovedstammen aabner sig paa
Kloakens indre Flade imellem et Par af dens stærke Folder.
Af den her givne Beskrivelse af de buskede Organer,
vil det sees, at de saagodtsom ganske svare til de, der
findes paa samme Sted hos Bonéllia viridis, og som Schmarda
har antaget for Respirationsorganer, idet han finder dem
analoge med Holothuridernes.
Lacaze-Duthiers har underkastet de nævnte Organer
en nøiere Granskning, og derved paavist, at de først og
fremst maa betragtes som et Kjertelapparat, som han
kalder Analsække (poches anales), imedens han dog opstiller
som en Mulighed, at de tillige kunne staa i Respirationens
From the description given above, it will be seen,
that the intestinal canal does indeed form numbers of
circumvolutions, but not, as in Bonéllia viridis (according, to
Lacaze-Duthiers), a spiral coil round the elongated uterus
(matrix, la poche génitale).
The whole of the buccal cavity was distended with
sabulous clay, containing divers Foraminifera, Diatoms, Algae,
and Ascaridæ. The gullet was empty; but immediately
posterior to that organ, part of the sabulous contents had
become moulded into cylindrical, elongated boli, rounded at
the extremities; and these fæcal pellets — 3.4mm long and
1.5—2mm broad — were found to increase in number, the
farther they extended down the intestine, the part between
the 5th transverse circumvolution and the anus being
entirely filled with them.
The two bunchy organs, almost globular in form and
3—4mm in diameter, are attached to the rectum, one on
either side, immediately in front of the cloacal opening,
fig. 8, a, a. They have a cylindrical trunk, forming a tube,
which at the point of origin is smooth for about lmm of
its length; but the remaining portion of the trunk sends
off numbers of tubular’ branches, from which issue a
multitude of long, slender, serpentine tubes, fig. 9, b, b. These
tubes have at their free extremity a funnel-shaped aperture,
leading to the hollow of the tube; the margin of the
aperture is furnished with long cilia, fig. 9, c, c; 10.
As regards their histological structure, these organs
are built up chiefly of the same elements as the intestinal
and cloacal walls, of which indeed they may be regarded as
a bossed expansion. The inner surface is clothed with
vibratile epithelium, projecting into the hollow of the tube;
and the cells, which are large, and in part round, in part
elliptical, contain a largish nucleus and a minutely
granulated brownish-green pigment, frequently so dense and opaque
as to entirely conceal the nucleus, figs. 12, a, a; 13, b, b.
The epithelium is webbed to a layer of fibrillous connective
tissue, adjoining the muscular integument, which consists of
longitudinal and annular fibres invested with the vibratile
peritoneum; the latter accordingly constitutes the exterior
surface facing the perivisceral cavity. In the lumen of the
tubes were seen numbers of free globose corpuscles,
somewhat shrunk or shrivelled, containing a nucleus or a few
granular molecules, fig. 13, c, and which resembled the
corpuscles in the perivisceral fluid, whereof part had coagulated
intq clots. The trunk itself opens on the inner surface of
the cloacum, between two of its prominent folds.
From the above description, it is obvious that these
bunchy organs almost perfectly correspond with the organs
.similarly located in Bonetlia viridis, which Schmarda held
to be respiratory tubes, analogous to the "trees" in
Holo-thurians.
Lacaze-Duthiers, who subjected these organs to a
more rigorous investigation, has shown them to be
fundamentally a glandular apparatus — anal sacs (poches
anales), though they may likewise, he thinks, in . some way,
be subservient to respiration. If so, one part would, in
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