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45
12 Bikanaler. Han siger: "I öfro delen af nedra
skaft-ansvällningen finna vi jemte de fvra hufvudkanalerna tolf
mindre langsgående bikanaler, hvilka omslutas af de
diko-iniskt klufna septa, der dessa fÖrena sig med skaftväggen."
Tegningen, som ledsager denne Beskrivelse, viser ogsaa
tydeligt denne dikotomiske Deling af Septa; men det er
en Misforstaaelse, naar det antages, at derved fremkomme
Lamgdekanaler paa dette Sted. I vore Figurer 30 og 31
er denne Deling af de 4 Septa henimod
Coenenchymvæg-gen fremstillet; men Delingen fortsættes eller rettere
forgrener sig og gaar over i det Maskenet, hvoraf Tverkanaler
i det hyaline Bindevæv dannes, Fig. 31 d. Langsgaaende
Bikanaler til de 4 Hovedkanaler fiildes ikke; det er kun
rummeligere Tverkanaler, som findes paa de Steder, hvor
Septa udgaa fra Ooenenchymet, hvilke Lindahl visselig
ogsaa, vilde have erkjendt som saadanne, om lian havde
havt Anledning til at udstrække den anatomiske
Undersøgelse noget videre.
Stokkens Coenenchvni er paa ile forskjellige Steder
mere eller mindre tykt. L den bulbøse Del er det 3 — 4mm
tykt og svampet; paa det smaleste Parti af Stilken er det
knapt l""". og paa den skedeformige Udvidning er det paa
Ventralsiden endnu meget tyndere. Fig. 3(1 h, imedens det
paa Dorsalsiden er meget tykt. 5—(i""". Fig. 3(1, /’; lignende
Forhold finder ogsaa Sted ved Rachis; men om end
Tykkelsen er forskjellig, saa er dog den indre Struktur ens
overalt.
0oenenchymets ydre Flade er overalt tapetseret meel
et temmelig tykt Epithel (Ectoderm), bestaaende af tiere
Lag polyædriske Celler, 0,008""" brede meel en stor, rund
Kjei ne og finkornet Protoplasiuaiiidhold, Fig. 37 a, 38 a,
39 a, 40 a: imellem disse polyædriske Celler sees ogsaa
mere aflange Celler af omtrent samme Størrelse. Omgivet
af Eetodermet og ligesom nedsænket i dette iagttages en
overordentlig stor Mængde temmelig klare, aflange Legemer,
som vi antage Ibr encellede Slimkjertler. De ere aflange, 0,040’"’"
lange, 0,024’""’ brede. Kjernen er stor, aflang, 0,008 lang,
0.006""" bred, Fig. 37, b. 38, b. 39, b. 40, /); di’ have en noget
forskjellig Størrelse paa de forskjellige Steder, ligesom de
i Regelen ligge enkeltvis; men nede paa den bulbøse Del
ligge de tildels som Drueklaser, og da kunne de være
stundom mere runde, stundom mere aflange, Fig. 41. Den
(hnstæudighed, at disse encellede Kjertier ere noget
nedsænkede i Epithelet, giver Overfladen ved mikroskopisk
l udersogelse Udseende af et Net, i hvis Masker
Kjertierne ligge, Tab. X, Fig. 59. De ere i naturlig Tilstand
næsten vandklare og have en temmelig .tynd Membran,
ligesom mange ere uden Kjerne, saa vi længe vare i Tvivl
om. hvortil vi skulle henføre disse Legemer; men ved
Farvning med Jodgrønt viste de sig aabenbart som
Celler; den store, aflange Kjerne traadte tydeligt frem, et
yderst finkornet Indhold, der omgav Kjernen, var
grøn-farvet. og endelig saaes paa enkelte, en tydelig
Udførsels-gang. hvis Aabning var traktforinig, Fig. 38, c. Disse
Kjertier findes overalt, ikke alene paa Stokken, men som
still, other 12 ductiferous branches. He says: "In the
upper part of the lower shaft enlargement, we find, besides
the four main canals, twelve smaller longitudinal branch
ducts, which are enclosed by the dichotomously divided
septa, where these attach themselves to the wall of the
shaft." The illustration which accompanies the description
shows, also, distinctly, this dichotonious division] of the
septa, but, it is a misunderstanding, when it is assumed that
longitudinal canals are thereby produced in this situation.
In our illustrations (tigs. 30 and 31), this division of the
4 septa in proximity to the wall of the sarcosoma is
represented. but the division is continued, or rather, ramifies,
and passes into the reticulation, which forms the
transverse ducts in the hyaloid connective tissue (tig. 31, d).
The longitudinal ductiferous branches to the 4 main canals
are not found; it is, only, wider transverse canals, which
are found in the situations, where septa issue from the
sarcosoma; and this, Lindahl would certainly have also
ackowledged to be the case, if he had had opportunity to
extend the anatomical examination somewhat further.
The sarcosoma of the stalk is more or less thick in
the various situations. It is 3—4""" thiele in the bulbous
part, and spongy; at the narrowest part of the stem, it is
barely 1""" thick, and on the ventral side of the sheath
formed dilation it is still thinner, (flg. 30, h) whilst, upon
the dorsal side it is very thick, 5—6"’"’ (fig. 30, /). A
similar relation is also found in the rachis, but, although, the
thickness is variable, the inner structure is everywhere
alike.
The sarcosoma’s exterior surface is, everywhere, coated
with a rather thick epithelium (Ectoderm), consisting of
several layers of polyhedrons colls, 0,008""" in breadth,
containing a large round nucleus and minute granular
protoplasma (figs. 37, a. 38, a. 39, a. 40, a.). Between these
polyhedrons cells, more oblong cells, but of the same size are
observable. Surrounded by the ectoderm, and embedded, as it
were, in it, a very large number of rather clear, oblong
bodies are observed, and these, we suppose to be single-celled
mucous glands. They are oblong 0,040""" long and 0,024"""
broad. The nucleus is large, and oblong, and measures
0.008"" long, and 0,006""" broad (figs. 37,/). 38,/). 39, b. 40. b.).
They have a somewhat varying size in the different situations;
whilst, as a rule, they are also situated singly; but, down in
the bulbous part, they are found situated, partly, like clusters
of grapes, and can then, occasionally, appear more round,
occasionally, more oblong (flg. 41). The circumstance that
these single-celled glands are somewhat depressed in the
epithelium, imports a reticulated appearance to the surface,
when observed under the microscope; the glands being
situated in the meshes of the reticulation (Pl. X fig. 59).
In the natural state, they are almost as clear as water, and
have a rather thin membrane, whilst, also, many appear
without nucleus, so, that for a long time, we were in doubt
what to consider these bodies; but, on being coloured with
iodine-green they proved themselves, indisputably, to be cells.
The large, oblong nucleus came prominently out; and an
extremely minute granular substance which surrounded the
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