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38
luvd med 30"" langt’ Tentakler. Udenom disse samtlige
Polyper paa venstre Side staa de 5 sture, laterale Polyper,
der llave sauime Storrelse som de tilsvarende paa hoire
Side, hvortil de fuldstændigt slutte sig og danne dermed
en sammenhængende King. Fig. 28.
Mati vil nu nf ovenstaaende Angivelse over
Polymernes Stilling bedst kunne erkjende, at uagtet det ved
en løselig Betragtning er umuligt at finde nogen bilateral
Symetri. er der dog tydelige Spor efter en saadan, der ved
den stierke Fordreining og Udvidning af Rachis, som igjen
er betinget af Knlkaxens Dreininger, har tabt meget af
Karakteren. Opgives dell bilaterale Symetri, som man for
endel kan gjöre saavel paa dette Exemplar som paa No.
8. <1 og II. saa vil man ved lidt Imagination faa
Polyperne til at være stillede i Ringe rundt Rachis, saaledes at
de store, laterale Polyper danne den yilre Ring, at de
dorsal-laterale Polyper rituim- en Ring indenfor denne,
hvorved den anden Rings Polyper staa afvexlende imellem den
ydre Rings, og saa fremdeles; men jo lifligere man kommer
ind ...... Centrum, jo vanskeligere bliver det at fastholde
Ringdanuelsen: thi Uregelmæssigheden i Stillingen bliver
altfor stor.
Polyperne luive forovrigt samme Karakterer som de
Foregaaende. Naar undtages et Par af de mindste
Polyper, have Alle udviklede Generatioiisorganor. De
ere Hunner, have Æg i alle Udviklingsstadier og enkelte
Embryoner, saa det er sandsynligt, at UmbeVula mainm
føder levende Uuger. I enhver Kapsel er del- i Regelen
kun et Æg.
Zooiderne danne i Regelen Here Rækker nedover paa
hele Stilken, saaledes staa de paa den bulbose Del indtil
dennes nederste Trediedel i 4. li.lt uregelmæssige Rækker
saavel paa Ventral- som Dorsalsiden; paa de laterale
Flader ere de sjeldnere.
Det maa hcmæl-kes, at paa samtlige de Exemplarer,
hvor Zooiderne strakte sig nedover Stilken, var Tentakelen,
i Regelen indtrukken, medens tiet modsatte var Tilfældet
paa dell skedeformige Udvidning og Rachis, — her var i
Regelen Tentakelen fuldstændigt udstrakt, hvorved disse Dele
fik ligesom et laaddent Udseende.
Pindested.
Station No. 31. Paa Station No. 176 fandtes et
Stykke af Axen nf et lidet Exemplar.
series of 3 polyps is observed (fig. 28, 111. Ill, 111), of
which, the posterior one (fig. 28. <■), is 50— long, and
8"" broad, and the tentacles measure 35— ill length.
Tin-other two diminish somewhat, in size, so that, the anterior
one of them, measures 35— in length, 5— in breadth, and
the tentacles 30— in length. Outside tin- whole of these
polyps, and on the left side, the 5 large lateral polyps
art-situated; these are similar in size, to the corresponding
ones of the right side, with which they completely unite,
and form, thus, an uninterrupted ring (fig. 28).
From the above description of the arrangement of
the polyps, it will be readily apparent, that upon a
superficial examination only, it is impossible to detect any
bilateral arrangement, but. that nevertheless, there are
distinct traces of such a bilateral symmetry; that, owing to
the strong twisting, and enlargement of the rachis; which
again, is conditional on the twisting of the calearous axis;
has lost much of its distinguishing characteristics. TI’ we
abandon the bilateral symmetry, which we may in a
measure do. both, relative to this specimen, as well as No.
8. II, and 11; we may, by a slight stretch of the
imagination, fancy the polyps arranged in rings round the rachis.
in such manner, that the large lateral polyps form the
outer ring, and the dorso-lateral polyps form a ring inside
it. by which, the second ring’s polyps become placed,
alternately. between the outer ring’s polyps, anil so on throughout;
but, the nearer we approach to the centre, the more
difficult does it become, to maintain the annular formation;
because, the irregularity in the arrangement becomes
excessive.
The polyps have, otherwise, the same characteristics
as the polyps of the preceding specimens. If we except a
couple of the smallest polyps, nil of them have, developed
generative organs. They are females, and contain ova in all
stages of development, and also, a few embryos, so that, it is
probable, that Umbellula eiiirimi» reproduces living young
ones. In each capsule, there is, as a rule, only one ovum.
The zooids on the whole of the stem, downwards,
generally fonn several series, so that, on the bulbous part
and to its lowest third part, they are situated, in 4
somewhat irregular series, both on the ventral and dorsal side.
They are not so numerons on the lateral surfaces.
it must be remarked, that in all the specimens,
where the zooids extended themselves down along the stem,
the tentacle was, generally, retracted, whilst, the opposite was
the case on the sheath-formed enlargement, and. the rachis.
There, the tentacle was, as a rule, completely extended, by
which these parts acquired it shaggy appearance.
Habitat.
Station No. 31. At station No. 17li. a portion of
the axis of a small specimen was obtained.
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