Fordøielsesorganerne. : 
Mundaabningen, der er rund og findes paa Midten af 
Mundskiven, er omgiyen af en Sphincter og fører ind til 
Svælget igjennem Atriet. Svelget er kort, eylindrisk, tem- 
melig muskuløst og har paa den indre Flade fremspringende 
Længdefolder. Hvor Svælget gaar over i Mayen er en ringe 
 Forengelse, men selve Mavesækken er ikke synderlig videre 
end Svælget, kun 'er dens forskjellige Hudlag noget tyndere. 
Tarmen har som sædvanligt 3 Bøininger, der ved 
Mesenterier ere fæstede saavel til Ryg- som Bugfladen, og 
gaar over i en lige Rectum, Fig. 8!, der ved mange musku- 
løse Baand er bunden til Kropsvæggen og ender i den 
runde Anus. Nogen Kloak findes ikke. 'Tarmens histolo- 
giske Sammenszetning frembyder intet synderligt Afvigende 
fra hvad der er almindeligt for Holothuriderne. 
stærkt udfyldt af Biloculiner. 
Den var 
Det indre Skelet. 
Kalkringen er meget fin, 17” i Gjennemsnit, og dan- 
nes af 10 Stykker, 5 Radial- og 5 Interradialstykker, der 
ere sammenbundne med et tyndt Bindevey, Fig. 15. Hvert 
Stykke bestaar af Tegemet (Corpus), Fig. 16, a, og den 
forlængede Del (Processus), Fig. 16, 0. 
Radialstykkernes ydre Flade er paa Midten forsynet 
med en Længdeture, Fig. 15, a, 16, c; deres indre Flade 
er lidt konkay, den bagerste Rand har et lidet Indsnit, 
som, idet det forener sig med det tilsvarende Interradial- 
stykkes bagerste Rand, der har et lignende Indsnit, bliver 
halvmaaneformigt, Fig. 16, d. 
Paa Ringens bagerste Rang findes altsaa 10 saadanne 
halvmaaneformige Indsnit, der ere afbrudte ved 10 Par 
yderst smaa Fremstaaenheder, Fig. 16, e,e. Fra to af 
*Radialstykkernes forreste Rand udgaa to Processer, Fig. 15, 
b, b; fra de øvrige 3 udgaar kun en Proces, Fig. 15, c. 
De 3 Radialstykker, der hver bærer en Proces, tilhører 
Bugfladen, og disse Processer ere meget lange. De to, der 
hver bærer to Processer, hvoraf den ene er længere end 
den anden, tilhører Rygfladen, ere placerede en paa hver 
Side af et Interradialstykke, Fig. 15, d, der danner Ryg- 
gens egentlige Midte og findes imellem de to dorsale Længde- 
muskler. Hvor Processen udspringer fra Radialstykkets 
Legeme, der findes et lille Hul til Gjennemgang for Ra- 
dialnerven, og lige bag dette insererer Radialmusklen sig. 
Interradialstykkerne ere lidt convexe paa deres ydre, 
lidt konkave paa deres mdre Flade. Fra deres forreste 
Rand udspringer fra ethvert af dem en Proces. der er 
meget mindre end de paa Radialstykkerne. naar undtages 
det midterste ventrale Interradialstykke, der har den længste 
Proces af alle, Hig. 15, c. 
Naar Kalkringen er sammenbunden, udspringer altsaa 
these processes are very long. 
Digestive Organs. ’ 
The oral aperture, which is circular and located in 
the middle of the oral disk, is surrounded by a sphincter, 
opening into the cesophagus through the atrium. The æso- 
phagus is short, cylindric, and rather muscular, with pro-' 
jecting longitudinal folds on its inner surface. Where the 
æsophagus opens into the stomach, there is a slight constrie- 
tion, but the ventral sac is but little wider than the ceso- 
phagus; the various tegumentary layers composing its skin 
are, however, Somewhat thinner. 
The ‘conyolutions of the intestine are, as usual, 3 in 
number, attached by mesenteries to the dorsal and ventral 
surfaces, and open into a straight rectum, fig. 81, webbed by 
numerous muscular bands to the wall of the body, and ter- 
minating in the circular anus. There is no eloacum. The 
histological composition’ of the intestine does not differ 
materially from that in other Holothurians. The intestine 
of the specimen examined was full of Biloculine. 
The Caleareous Skeleton. 
The calcareous ring is exceedingly minute, measuring 
not more than 1”” in diameter. It is composed of 10 seg- 
ments, 5 radial and 5 interradial, webbed together by thin 
connective tissue, fig. 15. Each segment consists of a 
body (corpus), fig. 16, a, and an elongated portion, or pro- 
cess, fig. 16, b.' Nr 
The outer.surface of the radial segments is furnished in 
the middle with a longitudinal groove, fig. 15, a; 16, ¢; 
the inner surface is slightly concave, and its posterior mar- 
gin has a slight incision, which. on uniting with a similar 
incision in the posterior margin of the corresponding inter- 
radial segment, acquires a lunate appearance, fig. 16, d. 
The posterior margin of the ring has accordingly 10 
of these lunate incisions.’ and in the space between these 
incisions occur 10 pairs of exceedingly minute protube- 
rances. fig. 16, e, e. From the anterior margin of two of 
the radial segments issue two processes, fig. 15, b, b; from 
the remaining 3, but one, fig. 15, c. The 3 radial segments 
with one process each belong to the ventral surface, and 
The 2 pieces with 2 pro- 
cesses each, of unequal length, belong to the dorsal sur- 
face; they are placed one on either side of an interradial 
segment, fig. 15, d, which constitutes the central portion of 
the back and occupies the space between the two dorsal 
longitudinal muscles. At the point where the process 
springs from the body of the radial segment, is seen a small 
aperture, for the passage of the radial nerve, and imme- 
diately posterior to this orifice, is inserted the radial muscle. 
The outer surface of the interradial segments is shehtly 
coyvex. the inner slightly concave. From the anterior 
margin of each issues a process much smaller than are 
those on the radial segments, saving that springing from the 
middlemost ventral interradial segment, which is the longest 
of all the processes, fig. 15, c. 
From the anterior margin of the calcareous ring, 
