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32
men som senere bar faaet en fuldstændigere Løsning i
Vej-do vsky’s1 og Spengel’s2 Afhandlinger over Ægdannelsen og
Hannen hos Bonéllia viridis, og hvortil vi skulle tillade os
at henvise for ikke at gjøre os skyldig i Gjentagelser.
Længere bag vare Follikelgrupperne talrigere, Æggene mere
udviklede, Fig. 16, p; i enhver Follikel var et Æg, der
udviklede sig af en Centralcelle. Jo længere bag man kom,
desto mere ere Æggene udviklede, saa at henimod
Æggestokkens bagerste Ende findes de mest udviklede Æg, der
ved sin Væxt sprænger Follikelen og falder ud i
Kropshulheden, hvor det fuldender sin Udvikling.
Æggestokken hos Hamingia lignede en Samling
Drueklaser ophængte i et Baand.
Det fuldmodne Æg saaledes som det findes i
Ægge-beholderne og tildels i Kropshulheden har kun en Hinde,
som Lacaze-Duthiers og for ganske nylig Dr. Spengel har
paa vist hos Bonéllia viridis; den af Schmarda beskrevne
anden Hinde eller Membi’an, hvormed Ægget skulde være
omgivet, er utvivlsomt Follikelmembranen.
Indenfor Blommemembranen ligger Kimblæren med
Kimplet omgiven af Protoplasmakorn, og udenom disse
store Blommekorn. dentoplasmatiske Kugler (se Vejdovsky).
Ingen Hanner have vi fundet, uagtet vi vare meget
opmærksomme derpaa.
De ovenfor beskrevne Kjønsorganer afvige forsaavidt
fra Bonelliens, som der hos denne kun er en Uterils,
imedens Hamingia har to. Men derimod nærmer den sig just
derved til Slægten Thalassema. Omendskjøndt dennes
Anatomi, saavidt vi vide, ikke er tilstrækkelig bekjendt,
fremgaar dog af de Undersøgelser Max Müller3 har anstillet
over Thalassema gigas, at den har 2 Uteri, som Müller
rigtignok kalder Ovarier. Han angiver, at de findes paa
Bugfladen, ere langstrakte, indtil 2 Tommer lange og have
en kort Udførselsgang, der munder ud i to paa den ydre
Bugflade siddende yderst smaa Vorter. Paa disse Ovarier
har Müller iagttaget en lille Fremstaaenhed, hvorpaa han
tror at have seet en lille Aabning.
Diesing4 har imidlertid opfattet Forholdet rigtigere,
idet han benævner dem Uteri, uden at han dog omtaler
1 Ueber die Eibildung und die Männchen von BoneUia viridis.
Franz Vejdovsky. Zeitsclirift f. wissensch. Zoologie, 30 B. 1878,
pag. 487.
2 Dr. J. AV. Spengel. Beitrage zur Kenntniss der Gephyreen.
Die Eibildung, die Entwicklung u. das Männchen der Bonéllia.
Mit-theilungen aus der zoologischen Station zu Neapel. 1 B., 3 Heft, 1879.
3 Thalassema gigas, Max Müller. Observ. anat. de vermibus
quibus-dam maritimi8. 18.r>2, pag. 20.
* Revision der Rhyngodeen, Karl Diesing, 1859, pag. 772.
Lacaze-Duthiers, but which, on a subsequent occasion, was
made the subject of more exhaustive treatment in Memoirs
by Vejdovsky1 and by Spengel2 on the growth of the egg,
and the structure and economy of the males, in Bonéllia
viridis; and to these papers we beg leave to refer, with
the object of avoiding needless repetition. Farther back,
the follicular groups are more numerous, the ova in a
relatively advanced stage of development, fig. 16, p. In
every follicle was an egg, developing from a central cell.
The maturity of the ova progressing with their passage
down the ovarium, the posterior extremity contains of
course the most developed, which, after bursting the
follicle, drop through into the perivisceral cavity, and there
attain the final stage of development.
The ovary in Hamingia resembled bunches of grapes
attached to a piece of ribbon.
The fully mature egg, as found in the uteri, — and
(some) in the perivisceral cavity, — is enveloped in a
pellicle only, which Lacaze-Duthiers, and quite recently Dr.
Spengel, have shown to be also the case with Bonéllia
viridis; the second pellicle, or membranaceous envelope,
described by Schmarda as investing the egg, is unquestionably
the membrane of the follicle.
Underneath the membrane of the yolk, lies the
germinal vesicle, with the germinal speck, surrounded by
protoplasmatic granula, and without these granula large
yolk-globules, dentoplasmatic pellets (vide Vejdovsky).
No males were met with, though carefully looked
for.
The generative organs described above differ, we see,
from those of Bonéllia, inasmuch as the latter has but one
uterine pouch, whereas Hamingia is furnished with two
uteri. But in thus differing from one congener, the new
genus approximates another — Thalassema. True, the
anatomy of this genus is as yet imperfectly known; but
it nevertheless appears from Max Müller’s3 investigation
of Thalassema gigas, that the animal has two uterine
receptacles, which Müller, however, terms ovaries. These
organs, placed, he states, on the ventral surface, and
elongate in form, measuring as much as 2 inches in length, are
each furnished with a short eferent duct, that disembogues
through 2 minute, wart-like papillæ on the outer ventral
surface. On these "ovaries" Müller has observed a small
prominence, in which he believes to have detected a minute
opening.
Diesing,4 however, had a clearer apprehension of the
office performed by these organs, and terms them accord-
1 Ueber die Eibildung und die Männchen von BoneUia viridis.
Franz Vejdovsky. Zeitschrift f. wissensch. Zoologie, 30 B. 1878,
pag. 487.
! Dr. J. V. Spengel. Beitrage zur Kenntniss der Gephyreen.
Die Eibildung, die Entwicklung u. das Männchen der BoneUia.
Mit-theilungen aus der zoologischen Station zu Neapel. 1 B., 3 Heft, 1879.
3 Thalassema gigas, Max Müller. Observ. anat. de vermibus
quibus-dam maritimis. 1852, pag. 20.
4 Revision der Rhyngodeen, Karl Diesing, 1859, pag. 772.
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