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lem disse Celler, dels ved deres Grund lindes i større
og mindre Mængde isolerede, store, kuglerunde eller
pære-dannede Legemer, der ere 0,026™" brede, bestaa af en tyk,
gjennemsigtig Membran, have en stor Kjerne med Kjerne,
legeme, og et kornet seigt Indhold, der holdes sammen i
en Klump efter at være presset ud af Legemet, Fig. 10,
d, d. De runde Legemer have et halvmaaneformigt Indsnit
paa den Side, der vender ud mod Cuticula, Fig. 25, a, og
i dette Indsnit formene vi at have bemærket en rund
Aabning, der stundom var udfyldt af det seige Indhold, Fig.
10, e, c. De aflange pæreformige Legemer have en
Udfør-selsgaug, der gaar op imellem Epithelcellerne og kan
forfølges lige ud til Cuticula, Fig. 10, d. d.
Disse Legemer tindes saagodtsom overalt i Huden,
men i størst Mængde ere de dog paa Mundskivçn rundt
om Tentakelgrunden, hvor de ligge Side om. Side. Vi
anse dem for .encellede Kjertier, der afsondre Slim og
høre Epithellaget til, ihvorvel vi fandt enkelte hist og her
i det Epithelet tilgrændsende Bindevæv. Omendskjønt
disse Organer ere, saavidt os bekjendt, enestaaende hos de
hidtil undersøgte Holothurider, kunne vi dog ikke betvivle,
at deres Funktion er at forsyne Huden med den Slim,
hvoraf der findes en saa stor Mængde paa Legemets
Overflade.
Dr. Teuscher1 har i. Huden hos Holothuria tubulosa
fremstillet aflange Celler imellem Epithelcellerne, hvilke
han antager for at være Slimkjertler; ogsaa vi have seet
disse; men have ikké fundet, at de i nogen væsentlig Grad
adskille sig fra det Epithel, hvor imellem de Andes.
Ogsaa Semper* har paavist aflange Celler i Bindevævet, som
han kalder Slimceller; disse tindes jævnligen i
Bindevævslagene hos Slægterne Trochostoina, Irpa og Kolga; men vi
kunne ikke antage dem for Kjertier, da de, som vi
tidligere have antydet, ere Bindevævslegemer, der formentlig
tjene til at opretholde Bindevævet3.
Umiddelbart til Epithelet, men indenfor dette,
støder Bindevævslaget, der er temmelig bredt, hyalint og
forsynet med en Mængde Bindevævslegemer, Fig. 10, e, e,
der paa enkelte Steder ligge tæt ved hinanden; de have en
forskjellig Form, snart ere de ovale med en eller to
Udløbere, snart næsten runde, og snart have de et kornet
Indhold, og svare da ganske til Sempers Slimceller. Det
er ganske mærkeligt, at Bindevævslaget er gjennemgaaende
hyalint, meget kjærnerigt, uden at være fibrillært, hvilket
ikke er almindeligt for Holothuridernes Hud, der jo altid
har et tykkere eller tyndere Lag fibrillært Bindevæv.
1 Jcnai8che Zeitschrift, 10 B&nd, pag. ">.">8. Jena 1870.
4 Reisen im Archipel der Philippinen, 2 Theil, 1 Band, pag. 165.
Leipzig 18<»8.
s Nyt Magazin for Naturvidenskaberne, 24de Bind, pag. 231.
Christiania .1878.
termination, fig. 10, b. Dispersed between the cells and
at their bases, occur an indefinite number of large,
isolated, globose or pyriform corpuscles, 0.026’"" in breadth.
These corpuscles consist of a thick diaphanous membrane,
investing a large nucleus and a nucleolus, the contents of
which, a viscid, granulous substance, if squeezed out, will
adhere together in a lump, fig. 10, d. d. The globular
corpuscles exhibit a lunate incision on the part facing the
cuticle, fig. 25, a; and in this incision there would appear
to be a circular aperture, sometimes filled with the
aforesaid glutinous mass, fig. 10, c, c. The ovate, pyriform
corpuscles are provided with an excretory canal, which,
protending upwards between the cells of the epithelium, may
be traced straight to the cuticle, fig. 10, d, d.
The skin, is almost everywhere studded with these
corpuscles; they are most numerous however on the
buccal disk, bordering the base of the tentacles, where
indeed they approximate, being there placed side by side.
We regard these corpuscles as secretory unicellular glands
belonging to the epithelium; a few do, however, occur every
here and there in the connective tissue adjoining that
layer. These organs are, we conceive, peculiar to the
present species, having never, so far as we are aware,
been observed in any of the known Holothuriidæ; yet their
function must assuredly be to furnish the skin with the
mucous secretion so copiously diffused over the surface of
the body.
Dr. Teuscher1 has figured in the skin of Holothur
ria tubidosa, among the cells of the epithelium, ovate
cells, which he conceives to be mucous glands; we have
also discerned these cells, but have failed to detect any
essentially characteristic feature distinguishing them from
the cells of the epithelium, among which they åre dispersed.
Semper,* too, has shown the occurrence of ovate cells
in the connective tissue, which he terms mucous cells; they
are commonly characteristic of the connective tissue in the
genera Trochostoma, Irpa, and Kolga; but we cannot agree
in deeming them glands, since, as we indicated on a former
occasion, they must be merely corpuscles of connective
tissue, to which they are probably in some manner subservient.®
Adjoining, but within, the epithelium, extends the
layer of connective tissue, rather broad, hyaline, and
furnished with numerous corpuscles of connective tissue, fig. 10,
e, e. "which, in places, are crowded together; they vary in form,
some being ovate and some almost spheroid; others contain a
granulous substance, and hence are the exact analogue of
Semjper’s mucous cells. It is remarkable that the layer of
connective tissue in this species should be invariably hyaline,
abounding in corpuscles, without being in the slightest
degree fibrillous, ä feature not hitherto met with in the
skin of known Holothuriidæ, which is always distinguished
by a layer of fibrillous tissue, more oV less thick.
1 Jenai8che Zeitschrift, 10 Band, pag. 558. Jena 187ti.
’ Reisen im Archipel der Philippinen, 2 Theil, 1 Band, pag. 1(15.
Leipzig 1808.
* Nyt Magazin for Naturvidenskaberne, 24de Bind, pag. 231.
Christiania 1878.
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