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4
Segmentalorganerne ere to, temmelig lange, der fæste
sig som almindeligt lidt bagen for Analaabningen paa hver
Side af Retractoren, Fig. 2, c.
Spiserøret er meget tyndt og langt, og ligger ligesom i
en Fure paa Retractoren lige bag til det Sted, hvor dennes
Rødder forene sig, Fig. 2, d\ her gaar det over i Tarmen, der
gjør et Par løse Bøininger, Fig. 2, e, for derefter
spiral-formig at løbe bagtil, næsten imod Kropshulhedens Ende,
Fig. 2, /, hvor den bøier om, uden at være befæstet til
denne, og slynger sig saa atter spiralformig fortil imod
Kroppens Midte, Fig. 2, g, hvor den gaar over i en lang,
næsten ligeløbende Rectum, Fig. 2, h, der munder ud paa
Ryggen.
Tarmspiralen er ved enkelte tendinøse Traade
bunden til Kropsvæggen; men nogen særskilt Spindelmuskel
findes ikke.
Paa Spiserøret iagttages et langt slangeformigt,
re-tractilt Kai-, der bagtil imod Retractorens tvende Rødder
ender blindt; men fortil omgiver Svælget og danner
Vand-karringen, hvorfra Tentakelkarrene udgaa.
Nervestrængen løber langs Midten af Bugfladen, Fig.
2, i, afgiver en Mængde Sidegrene i sit Løb og danner
fortil omkring Spiserøret, som sædvanligt, en Svælgring,
hvorfra sendes Grene til Svælg og Tentakler.
Æggestokken er fæstet til den bagerste Trediedel af
Spiserøret, er i Begyndelsen baandt’ormig, men bliver snart
cylindrisk og danner ligesom et Rør, der slynger sig flere
Gange om Tarmen. Den indeholdt Æg i forskjellige
Udviklingsstadier, ligesom fuldmodne Æg enkeltvis svømmede
frit om i Kropsvædsken. De Exemplarer, vi undersøgte,
vare Hunner.
Undertiden bebor den Anneliderør, men sædvanligt
lever den uden noget saadant.
Pindested.
Station: 34, 40, 51, 87, 176, 200, 295. Nogle faa
Exemplarer paa hver Station.
Artskarakter.
Legemet cylindrisk, glasklart. Kroppen forsynet med
spredte, fine Papiller; dens Bredde i Forhold til
Længden som 1—20. Snabelen lige lang som Kroppen, besat
med yderst smaa spidse Papiller. Tentaklerne 8—10. En
Retractor.
Aspidosiphon armatum. n. sp,
• Tab. I, Fig. :>, ß; Tab. II, Fig. T—14. .
Kroppen cylindrisk, 8mm lang; den bagerste Ende er
tvært afskaaren og forsynet med et rundt Chitinskjold, Fig.
5, der er sammensat af Plader, af hvilke de, som danne
The segmental organs — 2 in number — are
comparatively long, and, as in other species, attached to the
body a little posterior to the anal opening, on either side
of the retractor, fig. 2, c.
The oesophagus is exceedingly thin and long, and
extends, as it were, down a furrow in the retractor, back
to the point at which the roots of the latter unite, fig 2, d,
where it passes on into the intestine, which, after one or
two lax convolutions, twists spirally back almost to the end
of the perivisceral cavity, fig. 2, /; here it bends over, but
without being attached to the latter, winding spirally on
towards the middle of the body, fig. 2, g, where it enters
a long and almost straight rectum, fig. 2, h, which
disembogues on the back.
A few tendinous filaments web the spiral of the intedtine
to the walls of the body; but there is no separate fusiform
muscle.
On the ossophagus is seen a long, sinuous, retractile
vessel, with a csecal termination in close proximity to the
roots of the retractor, but anteriorly encircling the gullet
as the vascular ring, from which issue the. tentacular
vessels.
The nervous chord extends along the middle of the
ventral surface, with numerous subsidiary branches, forming,
as usual, round the oesophagus anteriorly a pharyngeal
ring, from which branches proceed to the gullet and the
tentacles.
Anteriorly, the ovary is webbed to the posterior third of
the oesophagus; at first riband-shaped, • it soon becomes
cy-lindric, constituting, as it were, a tube, that winds repeatedly
round the intestine. It contained ova in various stages of
. development; also mature ova, floating here and there in
the perivisceral fluid. The specimens we examined were all
of them females.
This animal sometimes takes up its abode in the house
of an Annelid, but is generally found to dispense with
such an habitation.
Locality.
At Stations 34, 40, 51, 87, 176, 260, 295; a few
specimens at each station.
Specific Character.
Body cylindrical, hyaline. Trunk furnished with
minute, distant papillæ; its breadth compared to its length as
1 to 20. Proboscis, equal in length to trunk, studded with
exceedingly minute pointed papillæ. From 8 to 10 tentacles.
One retractor.
Aspidosiphon armatum, n. sp.
Pl. I, figs. 5, 6; Pl. II, figs. 7—14.
Body cylindrical, 8mm long; posterior extremity truncate,
and furnished with a round chitinous shield, fig 5, composed
of plates, those forming the rim oval (petaloid), with the
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