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27
Bugkarret tager sit Udspring paa Tarmens Bugside,
i Niveau med Rygkarret, er meget fint ved sit Udspring,
tjltager i Tykkelse paa den anden (foranløbende) Slynge,
Fig. 3, «, og afgiver en Mængde Sidegrene til Tarmen, der
som tidligere nævnt forene sig med Rygkarforgreningerne.
Mavens Rygkar, der er tykkere end Tarmens, gaar
fortil langs Mave og Svælg og bidrager til i Forening med
Bugkarret at danne en Ring omkring Svælget, lige bag
Vandkarringen. Det afgiver Sidegrene, som netformig
udbrede sig paa Maven og Svælget, hvor de anastomosere med
Bugkarrets Forgreninger. Bugkarret er omtrent dobbelt
saa tykt som Rygkarret, Fig. 3, m, og afgiver lignende
Grene, som dette. Mavens Bugkar synes at udspringe med
mange smaa Grene fra Mavens bagerste Ende, hvor denne
gaar over i Tarmen uden at have nogen direkte Forbindelse
med Tarmens Bugkar.
Kjønsorganerne ere fæstede med et meget langt, fast
og temmelig bredt Ligament til den dorsale Del af
Mesen-teriet, just paa det Sted, hvor Tarmen begynder, og bestaar
af to Hovedstammer, der forene sig til en Stamme, som er
bunden til det ovennævnte Ligament. Den ene
Hovedstamme laa imellem Tarmbugtningen, uden at være bunden
til denne, flotterede frit i Kropshulheden, og var den største,
Fig. 3. o; den dannes af et rundt, hult Rør, hvorfra udgaa
mange temmelig korte Grene, 4—6, der ere forsynede med
Smaablærer, saaledes at altid Enden af Grenen er delt i
to, Fig. 3, p. Den anden Hovedstamme er kortere og
fattigere saavel paa Grene som paa Blærer, og var ved sin
ydre Ende bundet til Kropsvæggen tæt ved Stenkanalens
Befæstning ved en temmelig lang Bindevævstraad.
Efterat begge Stammer have forenet sig til en fælles
Stamme, gaar denne slangeformigt og skjævt forover imod
Stenkanalen, hvor den fæster sig til dennes Mesenterium,
følger den et Stykke Vei, men skiller sig atter fra den for
at munde ud noget bagenfor to af Rygtentaklerne, Fig. 2, b.
Den fælles Udførselskanal er især paa den forreste Del,
hvor den gaar langs Stenkanalen, meget fast og har en
hvid glindsende Farve. Den indre Flade af Blærerne er
beklædt med Celler, hvori Æg saaes i forskjellige
Udviklingsstadier. Det er sandsynligt, at Kjønnet er adskilt,
ligesom hos Elpidia og Kolga; det Exemplar, vi have havt
til vor Raadighed, var en Hun; der var Intet, som tydede
hen paa blandet Kjøn.
Nervesystemet afviger neppe fra hvad der er
almindeligt for Holothuriderne. Vi have seet en Nervering, der
er temmelig smal, som omgiver den forreste Del af Svælget
strax bagenfor Mundskiven. Fra den udgik fine Grene til
Svælget og Mundskiven, ligesom enkelte større Stammer
gik over paa den indre Flade af Kropshuden imellem denne
og Længdemusklerne (1 for hver Længdemuskel), uden at
The ventral vessel originates on the ventral surface
of the intestine, in a plane with the dorsal vessel, is
exceedingly slender at its commencement, increasing in thickness
on the second convolution, fig. 3, n, and sending off
numerous lateral branches to the intestine, which, as already
stated, unite with the ramifications of the dorsal vessel.
The dorsal vessel of the stomach, which is thicker
than that of the intestine, takes a forward course,
passing along the stomach and the gullet, and contributes,
together with the ventral vessel, in forming a ring round
the gullet, immediately posterior to the water-vascular ring.
It sends off a number of lateral branches, which spread
over the stomach and the gullet as a vascular network, the
ramifications anastomosing with those of the ventral vessel.
The ventral vessel is almost as thick again as the dorsal
vessel, fig. 3, m, and branches in a similar manner. The
ventral vessel of the stomach would seem to have its origin
in numerous branchlets proceeding from the posterior
extremity of the stomach, where the latter opens into the
intestine, without however being directly connected with the
ventral vessel of the intestine.
The generative organs are attached to the dorsal
portion of the mesentery by an exceedingly long, rather broad,
and close-textured membranous ligament, at the exact point
where the intestine commences, and consist of two
trunklike appendages, coalescing into one. which is webbed to
the membranous ligament. One of these stems lay within
the intestinal convolution, but was not attached to it, —
floating freely in the perivisceral cavity; this was the
largest, fig. 3, o; it consists of a tube, from which proceed
numerous branchlets. from 4 to 6, furnished with vesicles,
in such manner that the extremity is always furcate, fig.
3. p. The other Stem is shorter, and less abundantly
provided alike with branchlets and vesicles; at its outer
extremity it was connected with the wall of the body, close
to the point of attachment of the sand-canal, by a rather
long filament of connective tissue.
The common trunk produced by the junction of the
two stems, winds obliquely forward to the sand-canal, with the
mesentery of which it is connected, accompanies it a short
distance, whereupon it strikes off. to disembogue a little
posterior to two of the dorsal tentacles, fig. 2, b. The
common excretory canal, more especially the anterior
portion, which passes along the sand-canal, is exceedingly
firm in texture, and of a lustrous white. The inner surface
of the vesicles was clothed with cells, containing ova in
divers stages of development. The sexes are most
probably separate, as in Elpidia and Kolga. The specimen
here described was a female; we could detect no feature
suggestive of bisexual organisation.
The nervous system will hardly be found* to differ
from that in other Holothurians. We observed a nervous
ring, rather slender, surrounding the anterior portion, of
the gullet, immediately posterior to the oral disk. From
its outer margin a number of delicate ramifications
proceeded to the gullet and the oral disk; and several
larger branches were sent off to the inner surface of the
4*
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