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8
melig langt fra hverandre, 26 i Antal, og ere ved deres
tykke Grunddel krandsformig omgivne af korsformede
Pedi-cellarier, der strække sig langt op over Piggene, Fig. 1.
Forøvrigt er Armenes Ryg besat med ligeformede
Pedi-cellarier, der ere spredte over den hele Flade og imellem
hvilke sees Tentakelrør.
Bugen er flad; Ambulacralfuren bred, forsynet med 2
regelmæssige Længderækker stærke Papiller, hvoraf de i
den yderste Række ere længst, Tab. III, Fig. 8.
Strax udenfor denne sees en Række lange, stærke,
langt fra hverandre staaende Pigge, 32 i Antal, hvis
Grunddels ydre Halvpart er tæt omsluttet af korsformede
Pedi-cellarier, Fig. 8, a. Det smale Belte, som findes mellem
den ydre Række Furepapiller og de lange Pigge, er kun
yderst sparsomt optaget af ligeformede Pedicellarier.
Langs Ambulacralfuren er der ved Grunden af de
indre Papiller store, langstilkede, ligeformede Pedicellarier,
af hvilke der som oftest sidder en enkelt ved hver Papille.
Saavel de korsdannede som tl£ lige Pedicellarier have
stor Lighed med dem, der findes hos Asterias stellionura,1
men afvige dog i enkelte Punkter; dette gjælder kun de
Pedicellarier, som findes paa Rygsiden.
De korsdannede ere meget mindre; Kjæverne ere kortere,
ikke saa stærkt hvælvede til Siderne, og imellem de forreste 2
store Tænder er der kun en liden Tand (hos Ast.
stellionura 3—4), ligesom der næsten ingen Afstand findes
imellem de to store Fortænder og Sidetænderne, der ere
omtrent lige lange, hvilket ikke er Tilfældet hos Aster,
stellionura. De korsformede Pedicellarier, der omgive de store
Pigge paa Randen af Armene og Bugfladen, ere derimod
fuldkommen lig dem hos Ast. stellionura.
De ligeformede Pedicellarier, der findes paa Ryggen,
have paa Kjævernes Forende to smaa Tænder, ligesom deres
indre Flade er besat med fine Tænder, Tab. II, Fig. 3. 4.
Hos Ast. stéäionura have vi ikke kunnet opdage de to
smaa Fortænder; forresten kunne vi henvise til Tegningerne.
Hudskelettet er meget stærkt bygget. Paa Skivens
Ryg dannes det af uregelmæssigt formede Kalkstykker, der
dels ligge paa hverandre, dels støde umiddelbart til
hverandre og danne kun smaa Mellemrum for Gjennemgang af
Tentakelrør, Tab. II, Fig. 2, a.
Paa Armene have de Kalkstykker, der bære den
midterste Række Pigge, en oval Form og ligge taglagte paa
hverandre i en enkelt Rad, og til dem støde de
paatvers-løbende Kalkbjelker, der ere sammensatte af langstrakte,
smale Kalkstykker, Tab. II, Fig. 2, b, Tab. III, Fig. 9, a.
Her er et udpræget Kalknet, bestaaende af større og mindre
Masker, hvoraf mange af de til Siderne ere saagodtsom
They are 26 in number and are situated at a considerable
interval from each other, and at the thick basal part, are
environed by cruciform pedicellariæ, projecting far above
the spines (Pl. II, Fig. 1). Otherwise, the abactinal surface
of the rays is beset with rectiform pedicellariæ spread over
the entire surface, and with tentacular tubes appearing
between them.
The ventral surface is flat; the ambulacral furrow
broad, and supplied with two longitudinal regularly formed
series of strong papillæ, of which, the longest ones are found
in the outer series (Pl. Ill, Fig. 8).
Immediately outside this series, there is a series of
long strong spines, 32 in number, and placed at
considerable intervals from each other; their basal exterior half is
closely encompassed by cruciform pedicellariæ (Pl. III, Fig.
8, a). The narrow border formed between the exterior
series of furrow-papillæ and the long spinés is only
extremely sparingly beset with rectiform pedicellariæ.
Along the ambulacral furrow, at the base of the internal
papillæ, large, long-pedunculated, rectiform pedicellariæ are
visible, of which, most frequently, a single one is seated
beside each papilla.
Both the cruciform pedicellariæ, and the rectiform
pedicellariæ, have much similarity with those found in
Asterias stellionura/ yet differ in some points; that, however,
only refers to the pedicellariæ found on the abactinal surface.
The cruciform pedicellariæ are much smaller; the jaws
are shorter, and not so much arched laterally; and between
the two large front teeth, there is only a small tooth; (Ast.
stellionura has 3—4) there is almost no interspace between
the two large front teeth and the lateral teeth, which are
about uniform in length; and this does not occur in Ast.
stellionura. The cruciform pedicellariæ which environ the
large spines of the margin of the rays and the ventral
surface, are, on the other hand, exactly similar to those
of Ast. stellionura.
The rectiform pedicellariæ of the abactinal surface,
have two small teeth in the front of the jaws, whilst the
interior margin is occupied by minute teeth, (Pl. II, figs.
3, 4). We have not been able to discover the two small
front teeth in Ast. stellionura; as for the rest, the drawings
speak for themselves.
The dermal skeleton is very strongly constructed. In
the abactinal disk, it is formed of irregularly shaped
calcareous ossicles, partly covering each other, and partly
abutting upon each other, leaving only small interspaces
for the passage of tentacular tubes, (Pl. II, Fig. 2, a).
In the rays, the ossicles which carry the mesial series
of spines have an ovate form, and are placed in a single
imbricate row, upon which the transverse calcareous rods
abut; the calcareous rods are composed of elongate, narrow
ossicles (Pl. II, Fig. 2, b. Pl. Ill, Fig. 9, a). There is,
in this situation, a marked calcareous reticulation, consisting
of larger and smaller meshes, of which, many of the lateral
Se Tab. IV.
vide Pl. IV.
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