rørformige Forlængelser, som strække sig fra den ydre 
Rand til den hvælvede glatte Del af Skiven, Fig. 1,c, 2, ¢, 
— og der, hvor de ophøre, findes en skarp Fordybning, 
som adskiller den hvælvede indre Del af Skiven fra dennes 
ydre Del, Fig. 2, b. Imellem disse Forlængelser sees af- 
lange Fordybninger, der ere bredere udad, Fig. 1, d, 2, d, 
og i disse Fordybninger iagttages ligesaa mange yderst korte 
— mnæsten rudimentære — tredelte Tentakler, Fig. 2, e. 
Naar Dyret er udstrakt, saa er ogsaa de rørformige For- 
længelser opsvulmede og hvælvede, og da faar Legemets 
forréste Del Lighed med et Hjul, hvis Centrum dannes af 
Munden, Peripherien af Mundskivens ydre Rand, og Ra- 
, dierne af de rørformige Forlængelser. 
Legemets Overflade er ved 5 Par Længdemuskler 
delt i 5 Felter, hvoraf 2 tilhøre Rygsiden og tre Bugsiden. 
Lizengdemusklerne strække sig fra den forreste lige ud til 
Spidsen af den bagerste Ende. Hvert Muskelpar er adskilt 
ved et Mellemrum af omtr. 1”” Bredde, Fig. 1, e. 
Huden. 
Huden er bygget som hos Holothuriderne i Alminde- 
lighed. Cuticula, der danner det yderste Lag, er elat, 
gjennemsigtig og strukturløs, Tab. VIII, Fig. 19, a. Epi- 
thelet eller Subcuticularlaget, der ligger indenfor, dannes 
af Cylinderceller, Fig. 19, 0. Indenfor dette er Corium, 
der er omtrent 0.37” tyk paa Midten af Legemet. medens 
den imod begge Ender bliver indtil 0.57”, 
Den egentlige Læderhud bestaar af en temmelig fast 
Bindeværvssubstants, i hvis ydre Lag findes forskjelligfor- 
mede Kalklegemer, samt Pigmentceller, Tab. VIII, Fig. 16, 
17. Dette ydre Lag er tæt sammenvævet af Bindevævs- 
fibriller, som krydse hverandre i forskjellige Retninger, Tab. 
VIIT, Fig. 19, c, og sammenkittes af en hyalin intermediær 
 Substants. Pigmentcellerne have Udløbere og ere fyldte 
med et mere eller mindre mørkeviolet Farvestof, der ogsaa 
paa enkelte Steder findes i mindre Klumper udenfor Cel- 
lerne. Disse Klumper ere temmelig spredte paa en stor 
Del af Læderhuden, imedens de paa enkelte Steder ere lei- 
rede meget tæt sammen, hvor de endog ligge i Rækker. 
Det indre Bindevævslag, Tab. VIII, Fig. 19, d, er 
yderst smalt, hyalint, har hist og her enkelte Fibre, der 
synes at være Fortsættelser fra det ydre Lag, og er spar- 
somt paa smaa runde Kalklegemer. Ved at behandle et 
Tversnit af Huden med Reagentser, nemlig enten Eosin 
eller Picrokarmin, Glycerin og en fortyndet kaustisk Kali- 
dud, differentserer de forskjellige Væv sig saavidt, at det 
- bliver muligt at iagttage dem, og da sees: under stærk For- 
størrelse (Gundelach No. VI—I) i det indre hyaline Binde- 
vævslag baade forgrenede Bindevævsceller, Tab. VIII, Fig. 
36, og mere eller mindre aflange, temmelig klare Celler, 
by 15 tubular prolations, extending from the outer margin 
to the smooth arcuate section of the disk, fig. 1, ¢; 2, c; 
and at the point where they terminate is seen a well 
defined furrow, which separates the inner arcuate portion 
of the disk from the outer, fig. 2, b. Between these 
lations are seen a number of oval eavities, broadest exter- 
nally, fig. 1, d; 2, d; and these cavities contain each an 
exceedingly short — almost rudimentary — tripartite ten- 
tacle, fig. 2, e. When the animal blows itself out, the tubu- 
lar prolations also become swollen and arcuate, which gives 
to the anterior part of the body the appearance of a wheel, 
the mouth representing the nave, the outer margin of the 
pro- 
oral disk the circumference, and the tubular prolations the 
spokes. 
face of the body into as many sections, 2 
to the dorsal and three to the ventral surface. The longi- 
tudinal muscles extend throughout the whole length of the 
body, from the anterior to the posterior extremity. A 
space about 1”” in width intervenes between each pair of 
Five pairs of longitudinal muscles divide the sur- 
of which belong 
muscles, fig. 1, e. 
Skin. 
The composition of the integument is that common 
to Holothurians. The cuticle, forming the outer layer, is 
smooth, translucent and structureless, Pl. VIII, fig. 19, a. 
The epithelium, or subcuticular layer, extending beneath 
it, consists of cylindric cells, fig. 19, 6. Underneath the 
latter is the corium, about 0.3”” thick in the middle of 
the body and 0.5”” near both extremities. 
The corium consists of rather firm connective tissue, 
in the outer layer of which are dispersed calcareous spi- 
cules, differmg in form, and pigmentary cells. Pl. VIII, 
figs. 16, 17. This outer layer is built up of closely inter- 
woven fibrils of connective tissue, which intersect one an- 
other im various directions, Pl. VIII, fig. 19, c, 
The pigmen- 
a hyaline 
substance joining them, as it were, together. 
tary cells are furnished with offshoots, and contain a more 
or less deep violet-coloured substance, which in some pla- 
ces occurs as small lumps ‘outside the cells. These lumps 
are a good deal scattered throughout a considerable por- 
tion of the corium, but exceedingly close in some places, 
where they even constitute distinct series. 
The inner layer of connective tissue, Pl. VIII, fig. 19. d, 
is very narrow, hyaline, with here and there a few fibrils, 
continuations apparently of the outer layer, and is but 
sparingly provided with small circular calcareous corpuscles. 
On treating a section of the integument with chemical 
agents, for instance eosine, picrocarmine. or glycerine and 
a diluted solution of caustic potash, the various tissues 
admit of being observed separately. and, when viewed under, 
a powerful magnifier (Gundelach No. VYI—-1), both ramose 
cells of connective tissue, Pl. VIII. fig. 36, and more 
or less oblong, brightish cells, containing an agglome- 
