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udgaa Prolongationer af Bindevæv imellem Nervefibrillerne,
hvilke ere forsynede med Bindevævslegemer i stor Mængde.
Man har her aabenbart et Perineurium svarende til det
hos de høiere Dyr.
Nervestrængen er sammensat af Nervefibriller i dens
centrale Dele; og i dens Peripheri, altsaa nærmest Skeden,
er et celluløst Lag, hvis enkelte Celler vare lidt aflange og
forsynede med en Kjerne, uden at det var muligt at
iagttage noget Protoplasmaindhold.
Uagtet Centralnervestrængen ligger særdeles nær
Legemets ydre Flade, synes den dog at være godt beskyttet
mod ydre Indvirkninger ved det stærke Bindevævslag, som
omgiver • den, ved den tykke Bindevævsskede og endelig ved
dennes mange Prolongationer imellem Fib rillerne.
Fra Centralnervestrængen udgaa mange Grene til Hud
og Muskler. Naar den er kommen fortil imod Svælget deler
den sig i to Grene, der slaa sig omkring Spiserøret og
danne derved Svælgringen, som er indesluttet i en
Bindevævsskede.
Kjønnet er adskilt. Æggestokkene ligge en paa hver
Side af Endetarmen, ere langstrakte med bladformige
Ind-skjæringer, Fig. 2, i, og have en temmelig tyk, fast
Ud-førselsgang, Fig. 2, k, der ligger overfladisk paa Rygsiden,
tager sin Begyndelse et lidet Stykke bagenfor Æggestokkens
frie afrundede Ende, Fig. 2, l, og aabner sig udad strax
ovenfor Appendicet, Fig. 2, k.
Paa hele Bugsidens Midtparti er et stærkt, bredt
Mesenterium, der binder Æggestokken til Kropsvæggens
indre Flade. Dette Mesenterium strækker sig langt fortil,
bliver smalere og ender omtrent der, hvor Kropshulhedens
bagerste Trediedel tager sin Begyndelse.
Æggestokken dannes af en stor Mængde aflange,
blæreformige Legemer med deres Udførselsgange, der aabne
sig i den store Udførselskanal, hvis Lumen er temmelig
vidt. Blærerne bestaa af en tynd Bindevævshud, der paa
den indre Flade har et kjernerigt Epithel, hvori Æggene
udvikle sig, og paa hvis ydre Flade saaes spredte
Muskelfibre, beklædte af Peritoneum.
Udførselsgangene havde et meget stærkere
Bindevævslag; Epithelet, som beklæder den indre Flade, bestod af
Cylinderceller, og paa Bindevævets ,ydre Flade var en rigere
Mængde Muskelfibre.
I mange af Blærerne vare næsten fuldt udviklede
Æg, i andre vare Æg i tidligere Stadier, og i atter andre
saaes ingen Æg, men kun Epithelbeklædningen.
Hvad nu Hannens Kjønsorganer betræffer, saa kunne
vi ikke meddele noget Væsentligt derom; thi Testiklerne
paa det Exemplar, vi undersøgte, vare temmelig
beskadigede ; vi bleve dog overbeviste om, at vi havde med en Han
at gjøre, saasom en Mængde ret vel vedligeholdte
Spermatozoer med deres korte Haler iagttoges.
produced filaments of connective tissue pass between the
nervous fibrils, which are abundantly furnished with
corpuscles of connective tissue. We have here indubitably a
true perineurium, the analogue of that organ in more
highly developed animals.
The centre of the nervous chord consists of nervous
fibrils, whereas the peripheral part, or that nearest the
sheath, is a cellular layer, the cells composing it being
slightly oblong in form, and furnished with a nucleus; we
failed however to detect any protoplasmatic contents.
Although the central nervous chord protends in close
proximity to the outer surface of the body, it would
nevertheless appear to be sufficiently well protécted, viz. by the
strong layer of connective tissue that surrounds it, by its
thick membranous sheath, and by the numerous filaments
produced from the latter between the fibrils.
The central nervous chord sends off a great many
branches to the skin and the muscles. Anteriorly, a short
distance from the gullet, it divides into two branches,
which, winding round the oesophagus, form the pharyngeal
ring, sheathed in connective tissue.
The sexes separate. The ovaries — one on either
side of. the rectum — are elongate in form, with petaloid
incisions, fig. 2, i, and have a firm-textured and comparatively
thick eferent duct, fig. 2, k, protending close to the
surface on the dorsal side; it takes its origin a little posterior
. to the free rounded extremity of the ovary, fig. 2, I, and
opens externally, immediately above the appendix, fig. 2, k.
The medial portion of the ventral surface is wholly
invested with a broad and strong mesentery, which webs
the ovaries to the inner surface of the wall of the body.
This mesentery, reaching a considerable distance forwards,
gradually narrows, and terminated at the commencement of
the posterior third of the perivisceral cavity.
The ovary is built. up of numbers of elliptical,
vesicular corpuscles, each with an eferent duct, opening into
the great excretory canal, the lumen of which is
comparatively wide. The vesicles consist of thin connective
tissue, having its inner surface covered by nucleal
epithelium, wherein the ova develop, and on the outer surface of
which were seen isolated muscular fibres, invested with a
peritoneal tunic.
The eferent ducts had a much stronger layer of
connective tissue; the epithelium clothing the inner
surface, consisted of cylindrical cells; and on the outer surface
of the connective tissue, the number of muscular fibres, too,
was greater.
Many of the vesicles contained almost fully mature
ova; in some, the egg was in various stages of development;
others exhibited no traces whatever of ova, being quite empty:
nothing was seen but the epithelial covering.
As regards the generative organs in the male, we
have nothing essential to communicate, since the testes
in the specimen examined had been much injured; we felt
convinced, however, that the individual in question was a
male, having observed a considerable. number of
spermatozoa, with their short caudæ, comparatively perfect.
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