Vandkarringen danner en temmelig smal Kanal, der 
ligger strax bagenfor Kalkringen, og omgiver det indknebne 
Spiserør lidt foran det Sted, hvor dette gaar over i Maven, 
Fig. 3, k. Fra Ringkanalen udgaa 5 Kanaler, 3 paa Bug- 
siden og 2 paa Ryggen. De to af Bugkanalerne, der ud- 
løbe fra Siderne, dele sig hver 1 3 Grene, hvoraf den 
største, der kan betragtes som Kanalens Fortsættelse, gaar 
til Siden, løber langs den indre Flade af Kropsvæggen lige- 
til den bagerste Ende og danner Længdekarret, hvoraf der 
altsaa er to, et paa hver Side af Bugen. De to andre 
Grene gaa til hver sin Tentakel, hvori de udbrede sig. 
Den tredie Bugkanal, ligesom Rygkanalerne afgive hver 2 
Grene, en til hver sin Tentakel. Fra Længdekanalernes 
ydre Væg udgaar en Gren til hver Fod, og uden at kunne 
angive det med fuld Sikkerhed, forekom det os, som om 
der paa den indre Veg, især paa den bagerste Del at 
Længdekarret, fandtes Udbugtninger, der laa nedsænkede i 
Huden og kunne svare til Fodampullerne hos mange Holo- 
thurider, Noget som virkelig finder Sted hos Elpidia ifølge 
Dr. Théels Angivelser. Længdekanalerne ere ligesaa tykke 
som selve Vandkarringen, og deres indre Flade er cilierende 
ligesom dennes. 
Den Poliske Blære er pæreformig, meget stor med 
en temmelig kort Stilk, der gaar som 
Vandkarringen paa Bugsiden, Fig. 3, I. 
Stenkanalen er temmelig lang, smal og slangeformig; 
sædvanlig over i 
dens yderste Ende er afrundet og fastyoxet til Huden ved 
den ydre Rand af den venstre Rygmuskel, just paa det 
Sted, hvor Mundskiven gaar over i Kroppen. Strax inden- 
for den fastvoxede Ende sidder Madreporpladen, der danner 
en knopformig Forhgining paa Stenkanalen. Madreporpla- 
den har en meneandrisk Overflade med Forhgininger og 
Fordybninger, og hvis Organisation ikke synes at afvige 
væsentlig fra Madreporpladen hos Trochostoma*. Fra 
Madreporpladen bugter Stenkanalen sig henimod Vandkar- 
ringen, hvor den udmunder paa Rygsiden ligeoverfor den 
Poliske Blæres Udmunding. Stenkanalen bestaar af et 
temmelig fast Bindevæv; men er uden Kalk. 
Blodkarsystemet frembyder intet Særegent. Tarmens 
Rygkar begynder i den Forsnevring, som findes der, hvor 
Maven gaar over i Tarmen; det følger nu dennes Slyng- 
ninger lige ned til Rectum. Paa denne Vei afgiver det en 
Mengde Sidegrene til Tarmen, hvilke anastomosere med 
Bugkarrets Forgreninger, og danne derved Netudbredninger 
i Tarmenes Vegge. Desforuden afgiver det Grene til Me- 
senteriet og en temmelig stor Gren til Kjønsorganerne. 
1 Se Magazin for Naturvid. 24 Bind. Christiania 1878. ° 
in Trochostoma.: 
Immediately posterior to the calcareous ring, a rather 
narrow canal, forming the water-vascular ring, encircles the 
constricted æsophagus, a little in advance of the point where 
the latter opens into the stomach, fig. 3, k. From the 
annular canal branch off 5 canaliculated ramifications, 3- 
on the ventral and 2 on the dorsal surface. Two of the 
ventral canals, which issue from the sides, divide each into 
3 branches, the largest of which may be regarded as the 
continuation of the annular canal; it takes a lateral direc- 
tion, running along the inner surface of the wall of the 
body straight to the posterior extremity, and forms the 
longitudinal vessels, which accordingly are two in number, 
one on either side of the belly. The two other branches 
proceed each to a tentacle, in which they ramify. The 
third ventral canal and the two dorsal canals divide each 
into 2 branches, proceeding to as many tentacles. From: 
the outer wall of the longitudinal canals a branch proceeds 
to every sucker; and it seemed to us, though we cannot give 
it as a fully determined character, that on the inner wall, 
and more especially on the posterior portion of the long- 
itudinal vessel, were sinuous processes, embedded in the 
skin, analogus to the pedal ampullæ in many Holothurians, 
and which, according to Dr. Théel, do actually oceur in 
Elpidia. The longitudinal canals are equal in thickness to 
the water-vascular ring itself, 
is, In common 
vibratile cilia, 
and their inner surface 
with that of the latter, furnished with 
The, -Polian yesicle is pyriform, very large, and has 
a rather short stem, prolonged, as in other ‘Holothurians, 
into the water-vascular ring on the ventral surface, fig. 3, Å. 
The sand-canal is rather long, narrow, and flexuous, 
its upper extremity being rounded, and connate with the’ 
skin at the outer margin of the left dorsal muscle, exactly 
where the oral disk passes into the body. Immediately 
beneath the connate extremity occurs the madreporie body, 
as a globular protuberance on the sand-canal. The madre- 
poric plate has a meneandrian surface, exhibiting a succession 
of eminences and depressions; its structure does not appear 
to be essentially different from that of the madreporic plate 
From the madreporic plate, the sand- 
canal winds on to the water-vascular ring, where it disem- 
bogues on the dorsal surface opposite to the outlet of the 
Polian. vesicle. The sand-canal consists of rather firm con- 
nective tissue, but exhibits no traces of calcareous deposit. 
The circulatory system is not distinguished by any 
peculiar feature. The dorsal vessel of the intestine has its 
origin in the constricted passage through which the stomach 
- opens into the intestine, accompanying the conyolutions of 
the latter down to the rectum. On its course it sends. off 
numerous lateral branches to the intestine, which anasto- 
mose with the ramifications of the ventral vessel, forming 
reticulated vascular assemblages on the intestinal walls. 
Branches also proceed to the mesentery, and one rather 
large ramification strikes off to the generative organs. 
' Vide Magazin for Naturvid. 24 Bind. Christiania 1878. 
