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9
enkelte kunne indtage næsten Dyrets hele Længde, idet de
udspringe fra Ryggens forreste Dele og fæste sig paa
Tarmens bagerste Ende. Fra Bugfladen gaa ogsaa nogle
enkelte kortere Bindevævstraade hen til Tarmen. Hvoj" denne
gaar over i Kloaken. danne Ringmusklerne en Sphincter.
Kloaken er oval langstrakt. Fig. 8./. fra 8—10"*" lang.
og har paa den forreste Del ved Siden af Tarmindgangen en
tragtformig Forlængelse, der kan være indtil 5"" lang. Fig.
8, g. Kloaken er bunden til Kropsvæggen ved en stor
Mængde muskuløse Traade. Fig. 8. h. og dens vide
Aab-ning er forsynet med en stærk Sphincter, der faar sine
Muskler fra Hudens Tvermuskler. Kloaken dannes af de
samme Lag som Tarmkanalen, kun ere saavel Muskulaturen
som det hyaline Bindevæv meget stærkere repræsenteret.
Dette sidste danner paa den indre Flade, hvortil Epithelet
støder, fremspringende Længdelister, dér bidrage til at forme
de store Længdefolder, som findes paa Kloakens indre Flade.
Imellem Længdefolderne sees mindre Folder, der gaa
paa-tvers. hvorved et rudet Udseende fremkommer. Disse
Tver-folder synes at være afhængige af Muskelvirksomheden i
Kloaken. da de ere temmelig uregelmæssige.
I vor Beskrivelse over Trochostoma Thomson)1 gjorde
vi opmærksom paa. at der i Tarmvæggene fandtes af og
til en indkapslet Nematode, og at det fuldt udviklede Dyr
hyppig var at træffe i Tarmindholdet. Noget lignende finder
ogsaa Stçd hos Kolga hyalina. I Tarmindholdet hos denne
sees enkelte fuldt udviklede Individer af en Nematode, der
er forskjellig fra den hos Trochostoma Thomsoni. Men
foruden disse enkelte udviklede Dyr. tindes der overalt i
Kroppens Hud indkapslede Individer, der ligge spiralformig
indesluttede i £n tynd Membran. Disse saaledes
indkapslede Orme ere dog saa spredte i den vdre Hud. at de
ingen synderlig Forstyrrelse syiies at frembringe der. Men
ganske anderledes forholder det sig med Tarmen; her
optræde de i større Mængde, ja hos enkelte Individer var der
i Størstedelen af den første Slynge, lige fra Maven og
henimod første Bøjning, en saa overordentlig Masse af disse
indkapslede Nematoder, at Tarmens Muskelhud var
saagodtsom ganske ødelagt. Tarmen var nemlig her særdeles
meget udvidet, og dens Vægge vare yderst tynde og
gjennemsigtige. næsten som et Flor. Den letteste Berørelse
foraarsagede. at Tarmen løsnede fra Maven, og det kan
ingen Tvivl være underkastet, at her var en pathologisk
Tilstand indtraadt, der visselig ender med Individets
Ødelæggelse. Ogsaa i Kloakens Vægge fandtes hos enkelte
Exemplarer en Mængde indkapslede Nematoder, uden at
vi kunde opdage andre Destruktioner, end at der. hvor
Nematoden laa indspunden. var en Sanule Muskelatrophi.
1 Nyt Magazin for Xftturv. 24. Bind, p. 238, Christiania 1878.
Den norske Nordhavsexpedition. Dauielssen og Koren: Ilolotluirider.
ceedingly long muscular filaments, most of which protend
throughout the entire length almost of the animal, having
their origin near the anterior extremity’ of the dorsal region,
and terminating at the posterior extremity of the intestine,
to which they are attached. A few shorter filaments of
connective tissue proceed from the ventral surface to the
intestine. At the point where the latter opens into the
cloacum, a sphincter is formed by the annular muscles.
The cloacum is ovato-elongate, fig. 8,/. from 8"" to 10""
long, and furnished on the anterior margin, in immediate
proximity to the outlet of the intestine, with a funnel-shaped
appendage, attaining in some individuals a length of 6"".
fig. 8, g. The cloacum- is webbed to the inner surface of
the trunk by large numbers of muscular filaments, fig. 8.
h, and its wide opening provided with a powerful
sphincter, composed of muscles branching off from the transverse
muscles of the integument. The cloacum is built up of
the same tegumentary layers as the intestinal canal, but
the muscles and the hyaline connective tissue are much
more developed. From the inner surface of the latter,
adjoining the epithelium, issue a number of projecting
longitudinal fillets, which contribute to the formation
of the broad longitudinal folds on the inner surface of
the cloacum. Between the broad longitudinal folds are
seen numerous smaller ones, transversely disposed, which
gives to the surface a tesselated appearance. These
transverse folds would seem to depend on muscular action in
the cloacum,’ being rather irregular in form and arrangement.
In our description of Trochostoma Thomsoni.l we
called attention to the fact, that in the walls of the
intestinal canal occurred now and again an incapsulated Nematoid.
and that fully developed examples of that animal were
frequently met with among the contents of the intestine.
This, with some modification, is likewise characteristic of
Kolga hyalina. Among the contents of the intestine are
seen here and there fully developed examples of a Nematoid.
differing however from that in Trochostoma Thomsoni.
But. exclusive of these fully developed animals, incapsulated
individuals, spirally coiled within a thin membrane, occur
everywhere in the skin of the trunk. In the outer
integument, these incapsulated vermicules are so sparingly
dispersed that no serious organic derangement would seem to
result from their presence. Not so, however.• with the
intestine ; here, they occur in larger numbers; nay, in some of the
individuals were found such enormous quantities of these
incapsulated Nematoids throughout the greater part of the
first convolution, from the pylorus to the first bend, that
the muscular integument of the intestine had been well
nigh worn away. The intestine was distended almost to
bursting, its walls being thin and diaphanous as a piece
of gauze. Tlie slightest touch sufficed to detach the
intestine from the stomach, and there can be no doubt
whatever that a pathological phasis had set in which must
inevitably have terminated in organic dissolution. In the walls
of the cloacum. too. some examples had numbers of incap-
1 Nyt Magazin for Naturv. Part ’H, p. 2:tø, Christiania 1878.
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