Under Beskrivelsen af Slægterne Trochostoma og Irpa 
gjorde vi opmerksom paa, at’ Stenkanalen var fastvoxet til. 
Huden, uden at gjennembore den; og at der havde dannet . 
sig en Madreporplade paa selve Stenkanalen, indenfor Til- 
hæftningspunktet, og: vi antydede, at denne Ordning min- 
dede om en -embryonal Tilstand. Hos Elpidiq er Nten- 
kanalen ligeledes fastyoxen til den’ ydre Hud; men hos den 
har ingen Madreporplade dannet sig, hvorved den end mere , 
end de to nævnte Slegter nærmer sig Larvestadiet, som 
først hos Kolga er fuldkommen vedligeholdt. 
Ihvorvel den paa Ryggen beskrevne Krave med de 6 
Papiller ikke staar i nogen direkte Forbindelse med Vand- 
karsystemet. saa maa de dog nærmest henføres dertil, da 
de svare til Holothuridernés Rygfødder. 
Paa den indre Flade af Kropshuden,. paa det Sted, 
der svarer til Kraven, findes et Hulrum, der er dækket af 
et Diaphragma, hvori sees 4:aflange Aabninger, to til hver 
Side, Fig. 8, 7, 12, h. Diaphragmaet er dannet af et 
temmelig ‘fast, hyalint Bindeveevslag, samt Muskelfibre, og 
har et Overtræk af det flimrende Peritoneum. Aabningerne 
ere forsynede med cirkulere Muskelfibre, der danne en 
Slags Sphincter, som bidrager til, at de kunne sammentræk- 
kes og udyides efter Omstændighederne. Borttager man 
Diaphragmaet, iagttages en aflang , Hulhed, der svarer til 
Kravens Form, og i hvis Bund sees 6 runde Aabninger for 
de hule Papiller. Saavel Hulrummet. som Hulheden i Pa- 
pillerne ere beklædte med et flimrende Fpithel, der er 
Fortsættelse af Peritoneums. Kravens Hulhed, ligesom Pa- 
pillernes, staa saaledes i umiddelbar Forbindelse med Krops- 
hulheden, og dennes Vædske cirkulerer derfor ind og ud 
af dem og bidrager til, at de udspændes og sammenfalder. 
Selve Papillernes Struktur er den samme som Føddernes, 
kun ligge Spiklerne noget mere adskilte fra hverandre, 
naar undtages de øverste Spidser,- hvor de ligge mere 
compakte. 
. 
Blodkarsystemet. 
De Blodkar, som strax springe i Øinene, naar Dyret 
aabnes, er Tarmens Ryg- og Bugkar, eftersom Sectionen 
sker fra Ryg- eller Bugsiden. Disse. Kar udspringe jo hos 
Holothuriderne i Almindelighed paa Grændsen imellem Mave 
og Tarm; men saa er ikke Tilfældet hos Kolga. Her tage 
de sit Udspring fra et ringformigt Kar, der omgiver Svæl- 
get, Fig. 8, m, strax bagenfor Vandkarringen og tildels 
dækket af denne.. På | | 
Blodkarringen, der er fin som'en Traad, afgiver fra 
dens forreste Rand Grene til Svælget og et: Par Grene til 
Vandkarringen; fra dens bagerste Rand udgaar en Gren, 
der bugter sig langs Spiserøret og Maven til Kjønsorga- 
When describing the genera Trochostoma and Irpa, å 
we called attention to the fact that the sand-canal was 
connate with the integument, which, however, it does not 
perforate, and that a madreporic plate had developed on 
the canal itself, within the point of attachment, intimat- 
ing that such organic arrangemerit was suggestive of an 
embryonic state. In Elpidia, too, the sand-canal is con- 
nate with the outer skin; but there is no madreporic 
plate, and hence it approximates more closely than ‘do 
either of. those genera to the larval stage, which in Kolga 
is’ perfectly maintained. Hen Ke 
The dorsal ‘protuberance, or eollar, with its 6 papil- 
‘lary warts, has, indeed, no direct connexion with the aquif- 
erous system, but must’ nevertheless be referred to that 
part of the organism, being the analogue of the dorsal 
-suckers in other Holothurians. 
On the inner surface of the integument, in juxtaposi- 
tion to the base of the collar. occurs.a hollow space, covered - 
by a diaphragm, in which are seen 4 oblong openings, two 
on ‘either side, fig. 8, 1; 12, h.» The diaphragm consists of 
a layer of rather firm, hyaline connective tissue, and of 
inuscular fibres, over which extends the ciliated peritoneum. 
The openings are furnished with circular muscular fibres, 
coustituting, as it were, sphincters, that assist, when need- 
On removing the 
diaphragin, an Oblong éxcavation is observed.. similar in 
form to the collar, and in the bottom of which are seen 6 
ful, in their contraction and expansion. 
vound apertures, for the reception of the hollow papille. 
This. hollow space, and the cavities of the papillae, are 
both covered with a ciliated epithelial membrane, a con- 
tinuation of that on the peritoneum. Hence, the hollow 
interior alike of .the collar and of the papille is in 
direct communication with the perivisceral cavity, afford- 
ing ingress and egress to its fluid, which, circulating 
freely through them, is partly the cause of their expansion 
and collapse.’ The papille have the same structure as 
the suckers; their spicule, however, are less closely set, 
saving those on the extreme points, where a denser arrange- 
ment is observed. | 
Circulatory System. 
‘On opening the animal, the blood-vessels first discern- 
ed are the dorsal and ventral vessels of. the intestine, ac-- 
cording as the section be made on the dorsal or yentral 
side. Now, these vessels originate in most Holothurians 
between the stomach and the intestine; but Kolga forms 
an exception to the general rule. In this genus, they issue 
gullet, - fig. 8, m, 
immediately posterior to the water-vaseular ring of the 
ambulacral. system, by which they are partly covered. 
The circlet of blood-vessels, which is slender as a 
fine-drawn wire, ramifies. on the anterior margin, divers 
branches protending to the gullet, and one or two to the 
from an .annular vessel encircling ‘the 
- water-vascular ring; from the posterior margin a flexuous 
