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vi senere skulle se. ogsaa paa Polyperne i en utrolig
Mængde, og det tykke, gelatinose Slim, der i levende Live
indhyller disse Dele. lader sig derfor let forklare.
Ectoderm-eellernes Indhold er tildels brunt pigmenteret; men dette
Pigment er mere eller mindre intens, saaledes er det paa.
den hulbose Del intensere end paa den ovrige Del af
Stilken.
Saavidt os bekjendt er der ikke hidtil fundet
Slim-kjertler hos Pennatuliderne, ihvorvel na’sten alle Søtjære,
naar man tager dem op af Soen. føles slimede; men ikke
hos nogen have vi iagttaget saa tykt. gelatinost Overtræk
som hos Uvibelhda emrinus, og derfor var det at vente,
at dei1 maatte findes særegne Organer for denne Afsondring.
Det tor nok hænde, at man herefter ved Afbenyttelsen af
Jodgront vil finde Slimkjertler hos mange Pennatulider;
thi det er ikke sandsynligt, at disse Organer alene skulle
findes hos UmbéUula eiurinu
Indenfor Ectoderinet er et Lag fast, fibrilkert
Hindevæv. hvori findes spiiulelformede Bindevævslegemer med
Kjerne, og hvis l’dlobere tildels korres])ondere med
hinanden, Fig. 37, c. 39, c. 40, c. Dette fibrillære Bindevæv
stoder til et meget bredt, hyalint Bindevætshig, der
indtager hele den øvrige Del af Coenenchymet, og hvori eier er
større og mindre Spalter, der danne saavel Lamgde- som
Tverkanaler. Lige ved den indre Kand af det fibrillære
Bindeva’v, eller der. hvor dette støder sammen med det
hyaline, findes i en enkelt Bække, men Side om Side,
Længdekanalerne, Fig. 36, b. 39. <1. Disse Længdekanålér
ere ikke lige vide; enkelte ere trangere end andre, og af
og til er en meget vid placeret imellem to eller Here trange,
Fig. 39. <■. Det fibrilkere Bindevæv danner i
Lamgdekana-lerne et listeforinigt Fremspring, der rager mere eller
mindre ind i Kanalen. Fig. 39. c. 40. d. ja ikke sjeldent
forlænger dette Fremspring sig helt igjennem denne,
hvorved den deles, og saaledes fremkomme de mindre Kanaler,
der da intet Fremspring have, Fig. 39, d. Men ret hyppigt
sees to saadanne Fremspring at rage temmelig langt ind i
Længdekanalen, der da sædvanligvis er meget vid.
Lamgde-musklerne ere fæstede ikke alene paa disse Bindeva’vslister
men ogsaa paa Kanalens Sidevægge, Fig. 39. /. 40, /, og
bestaa af temmelig stærke Fibre, hvorved Længdekanalen
kan forkortes. Man ser Virkningen af disse Lamgdemuskler
meget, godt udvendigt paa Coenenchymet. hvor Kanalerne
vise sig i fine Bugtninger langs hele Stilken; lettest
iagttages de dog paa dennes bulbøse Del. Længdekanalerne
ere paa deres hele indre Flade bekhedte med et. Epithel,
der bestaar af runde Celler med en klar, gjennemsigtig
Membran og en rund Kjerne omgiven af fine, na’sten klare
Protoplasinakorn. Cellerne ere 0,008""" og Kjernen 0,002"’"’,
Fig. 4o, g. Det hyaline Bindevævslag er meget bredt og
danner et Net af Tverkanaler. der lobe i alle Retninger
og give Coenenchymet sin svampede Karakter, Fig. 36. c.
39, g. 40. h. Dette hyaline Bindevæv er gjennemtrængt
af en stor Mængde fine Ernæringskaiialer, som forgrene sig
nucleus was tinged green, and finally, in a few; a distinct
excretory duct, whose aperture was funnel shaped (fig. 38, r).
was seen. These glands are everywhere found, not only
on the stalk, but, as we shall subsequently see, also, in
incredible numbers on the polyps, and the thick gelatinous
mucous, which in the live state enclosed these parts, becomes
therefore easily explainable. The contents of the ectoderm
cells are, partly, tinged brown, but the colour is variable
in intensity, so that, for instance, at the bulbous part, it
appears deeper than in the remainder ol’ the stem.
As far as we are aware, there have not, hitherto,
been found, mucous glands in the Pennatulida1. although,
nearly all sea-pens feel slimy when taken out of the sea;
but. in none, have we observed such a thick gelatinous
covering as in UmbelJula encr/mis; and, it was therefore
to be expected that special organs for this secretion would
be found. It may probably happen, hereafter, that by the
application of iodine green, mucous glands will be found
in many Penatulidæ; because, it is not likely that these
organs are found, exclusively, in Umliellula encrinus.
Inside the ectoderm, there is a. layer of compact
fibrillous connective-tissue, in which spindle-formed
connective-tissue bodies having a nucleus, are found, whose
prolongations, partly, correspond with one another (fig. 37 c.
39 c, 40 c). This fibrillous connective-tissue abuts, on a
very broad, hyaloid layer of connective-tissue, that
occupies the whole of the remaining portion of the sarcosonia.
and, in which larger and smaller fissures occur, which form
both, longitudinal and transversal canals. Exactly at
tin-inner margin of the fibrillous connective-tissue, or, at I lie
point where it unites with the hyaloid tissue, a single
series of longitudinal canals placed side by side, is found
(figs. 36, b, 39. d). These longitudinal canals are not
uniformly wide; some are narrower than others; and. now
and then, a. very wide one is situated between two or
more narrow ones (fig. 39, o). The fibrillous connective
tissue forms, a fillet-formed prominence in the longitudinal
canals, which projects more or less into the canal (figs.
39, e. 4o. d); indeed, this prominence prolongs itself, not
infrequently, quite through the canal, which thus becomes
divided, and produces the smaller canals which have
then, no prominence (fig. 39, d). Most frequently, however,
two such prominences are observed, to extend pretty far into
the longitudinal canal, which, then, is generally very wide.
The longitudinal muscles are attached, not only to these
connective-tissue fillets, but, also, to the lateral walls of
the canal (figs. 39,/. 40/); and consist, of rather strong
fibres, by means of which, the longitudinal canals may be
shortened. The, effect of these longitudinal muscles is very
well seen, externally, on the sarcosonia, where the canals
appear in fine windings along the entire stem; they are.
however, most easily, seen on the bulbous part of the
stem. The entire inner surface of the longitudinal canals,
is covered with an epithelium, consisting of round cells,
having a clear transparent membrane, and containing a
round nucleus, surrounded by minute, almost clear,
protoplasmic grains. The cells are 0,008’"’" in width, and the
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