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59
er bortrevet, sau at Axen er blottet i en Udsfcækning af
30»», hvor Bashis or afbrækket, Fin, «■ Men da vi
af (let meget ufuldkomne Exemplar dog kan faa saamegen
Oplysning, at vi med nogenlunde Sikkerhed kan bestemme,
at denne Snfjær ikke kan henfores til nogen af de bekjendte
Slægter, og da hertil kommer, at den synes at nærme sig
en Overgangsform, have vi troet det af Interesse at
beskrive den, hvor ufuldstændig end Beskrivelsen nødvendigvis
maa blive.
Naar vi have nævnt en Overgangsform, saa skulle vi
med nogle Ord begrunde dette. Vi have ikke iagttaget
hos nogen Pennatulide en saadan Rigdom af Kalk som
den, der tindes Ilos Gmmeria borealis. Sareosomaet danner
formelig en Kalkskorpe. Cellerne ere saa stierkt
incruste-rede af Kalkspiklor. at det selv ved kaustisk Kalilud har
sine Vanskeligheder at faa dem skilte fra hverandre, ■ og
Polyperne ere saavel paa Krop som Tentakler i en
overordentlig Grad opfyldte af Kalkspikler. Med Hensyn hertil
har jo Ommria adskilligt tilfælles ined Qorgoniderne; og
ser man hen til Spiklernes Fonn. især i Stilken, saa voxer
jo Fællesskabet noget; men med alt dette have vi dog for
os ell udviklet Pennatuliie, der nærmer sig meget til
Pro-toptilerne og maa vel henfores til deres Familie, nemlig
Piotoptm«■.
Den hele Stump er 103»» lang. hvoraf Stilken udgjor
52...... og Hachis, forsynet med Sarcosoma, 16»».
Efter de uudviklede Polypceller at domme, hvilke
væsentlig indtage dell Del af Rachis, som er bevaret, danne
tie skja’ve Riekker, der gaa fra Ventralfladen over pan den
noget hvælvede DorsaWade. som ganske indtages af Celler.
Fig. 8. I hver Række er der 4 -5 Celler, og i det yderst
smale Rum imellem Rækkerne sees enkelte mindre Celler;
men Zooider tindes ikke. Disse uudviklede Celler variere
noget i Størrelse; ile ere fra I—2"" lange og II,ti l""
brede foroven med en liden Aabning, hvis fri Baud er
forsynet med et forskjelligt Antal yderst fine Papiller. Fig. 8.
Cellernes indre Va’g er sammenvoxet med Sareosomaet.
Polyperne i disse Celler have en brunlig Farve, det
vil sige Svælget og (le 8 Gastralfilamenter ere brunlige;
Tentaklerne ere rudimentære. Strax ovenfor disse
uudviklede Celler sees til Venstre en næsten udviklet Celle med
sin Polyp, Fig. 8, g. og lidt længere oppe paa Dorsalsideil
sidder den eneste, fuldt udviklede Celle med Polyp, som
findes paa dette i hoi Grad defekte Exemplar. Fig. 8. b.
Den udviklede Celle er 3— lang, deus Aabning. hvis
fritstaaende Rand er forsynet med 8 tykke Papiller (Tænder),
er 2.5—, Fig. !). a. Cellens indre Væg er forstørstedelen
sammenvoxet med Sareosomaet; men Randen er fri og
rager lidt ud fra Rachis.
polyp, owing to the sarcosoma above being torn away, so
that, tile axis becomes exposed for a length of 30"», and
the rachis is then broken off (lig. 8). Hut, as the
incomplete specimen affords so much information, that we are
able with considerable certainty to satisfy ourselves that
this sea-pen can not be assigned to any of the known
genera; whilst, to this, comes to be added, that it appears
to approach to a transition-form; we have thought it of
sufficient interest to be described, however incomplete the
description must of necessity lie.
As we have mentioned that it approaches to a
transition-form, we will in a few words substantiate this. We
have not observed in any Pennahllida such an abundauee
of calcium as is found in Gunneiia borealis. Tile
sarcosoma forms, in fact, a calcareous crust. The cells are
so strongly encrusted with calcareous spicules that, even,
on treatment with a solution of caustic potash, it is no
easy matter to separate them from each other, and the
polyps, both, on tile body and the tentacles, are filled up in
an extraordinary degree, with calcareous spicules. In this
respect indeed, Glmncria has much in common with
Qorgonidæ, and if we regard the form of the spicules,
especially, on the stem, the resemblance becomes still more
prominent, but, nevertheless, we have before us a developed
Petliiatldida which approaches, much, to the Protoptili, and
must, without doubt, be assigned to their family, namely,
Protoplilidæ.
The entire fragment measures. 103»» in length; of
this, the stem occupies 52"». and the rachis — furnished
Judging from the appearand’ of the polyp cells
which, principally, occupy the portion of the rachis that
is preserved, they form crooked series, proceeding from
the ventral surface over to the somewhat arched dorsal
surface, which is quite occupied by cells (fig. 8). In each
series there are 4—5 cells, and in the extremely narrow
space between the series, a few smaller cells are seen, but
no zooids are found. These undeveloped cells vary much
ill size; they measure from I— 2— long, and from 0.6—1.0—
broad, above; and they have a small aperture, whose free
margin is furnished with, a varying number of extremely
minute papilla; (fig. 8). The inner wall of the cells is
concreted with the sarcosoma.
The polyps in these cells have a brownish colour,
that is to say: — the gullet, and the 8 gastral filaments are
brownish. The tentacles are rudimentary. Immediately
above these undeveloped cells, a nearly developed cell with
its polyp, is observed to the left (fig. 8, a), and a little
further up, on the dorsal side, the only fully developed
cell and polyp which is found in this highly defective
specimen, is seen situated (fig, 8, V)
The developed cell is 3»» long, and the aperture is
2.5 broad; whilst, the free independent margin is furnished
with 8 thick papilla? (teeth) (fig. 9, a). The greater part
of the wall of the cell is concreted with the sarcosoma.
but the margin is free, and protrudes a little from the
rachis.
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