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16
i Tykkelse, indtil den opimod den øverste, udvidede Ende
bliver kun 0,5""" tyk, Fig. 1. Den øverste Del af
Stokken er krumbøiet og i en Længde af 8""" skedeformet
udvidet langs Dorsalfladen, Fig. 1. 2. 3. Denne
Udvid-ning er bredest, hvor den gaar over i Hachis — 2 til
3""" — og aftager successivt nedover. Stilkens Sarcosoma
er temmelig tyndt og halvt gjennemsigtigt overalt, naar
undtages den bulbøse Del, hvor det er tykkere og opakt.
Paa den øverste, skedeformige ITdvidning sees enkelte
Zooi-der, der staa som smaa, runde Perler med en lille
Aabning paa Midten.
Hachis har baade en Side- og Længdekrumning, er
6""" lang og omtrent 3""" bred.
Dorsalfladen er næsten plan, temmelig smal og tæt
besat med Zooider, Fig. 2, a. Ventralfladen er stærkt
hvælvet, danner en Kjol paa Midten, der er glat, Fig. 3, a,
og til hver Side et lidet Skraaplan, som er tæt besat med
Zooider, Fig. 3, b. Sidefladerne, der ere meget smale,
optages af 2 lancetformige, noget ophøiede Zooidefelter,
der strække sig op imellem Polyperne, Fig. 2, b, saaledes,
at der paa hver Side er et Felt imellem 2 Polyper og et
andet imellem en Polyp og Dorsalfladen. Disse Felter,
der komme tydeligere frem og forøges i Antal, alt eftersom
Dyret udvikler sig’, og Polypernes Antal tiltager, ere
vistnok de samme, som Mylius i sin Beskrivelse kalder
Bægerets lancetformige Blade, og som gjenkjende« baade paa
hans og Ellis’s Afbildninger.
Hachis bærer 5 Polyper, af hvilke den ene danner
en fuldstændig Endepolyp, der udspringer fra den øverste
Spids af Hachis, Fig. 2, c. 3, c, og af de 4 øvrige udgaa to
paa liver Side, dog nærmere Rygfladen, Fig. 2, d. 3, d,
hvorved en udpræget bilateral Symetri kommer tilsyne.
Endepolypens Krop er 5""" lang og omtr. 2""" bred;
Tentaklerne næsten dobbelt saa lange. De 3 Sidepolypers
Krop er næsten 7""" lang og 2,5""" bred; men den 4de har
samme Størrelse som Endepolypen; Tentaklernes Forhold
til Kroppen er det samme som hos Endepolypen.
Polypernes Krop er cylindrisk, glat og har 8 temmelig brede
Længdelinier, der antyde Insertionerne for Septa. Ved
Grunden af Endopolypen. nærmest Dorsalfladen, sees en
liden, knopformig Forhøining, der er en Polyp i Udvikling,
Fig. 2, c.
Mundskiven er hvælvet, og i dens Midte sees en
aflang Mundspalte, der er forsynet med 8 temmelig tykke,
lancetformige Læber, som paa Midten af den indre Flade
have en Fure.
Axen strækker sig fra Grunden af den bulbøse Del
til Stokkens øverste Ende. Paa denne Vei indtager den
Midten af Stokken op imod den øverste, krumbøiede,
ske-deformig udvidede Del, hvor den nærmer sig saa meget
Ventralsiden, at det ser ud, som om den gaar ind i selve
a breadth of 2"""; subsequently, gradually diminishing i
thickness, until, the thickness towards the superior
expanded extremity becomes reduced to only 0.5""" (fig. 1).
The superior part of the stalk is bent, and for about 8"""
of its length, is dilated in a sheath-form, along the dorsal
surface (figs. 1. 2. 3). This dilation is widest, at the
point where it passes over into the rachis — 2 to 3’"’"
wide — and becomes gradually narrower downwards. The
sarcosoma of the stem is rather thin, and everywhere,
semi-translucent, except at the bulbous part, where, it is
thicker and opaque. On the superior sheath-formed
dilation, a few zooids are visible, appearing like small round
pearls, with a small aperture in the middle.
The rachis is curved, both longitudinally and
laterally; and is 6""" long and about 3""" broad.
The dorsal surface is nearly flat; rather narrow, and
closely beset with zooids (fig. 2, a). The ventral surface
is sharply arched; and forms a ridge in the middle which is
smooth (fig. 3, a), and on each of its sides, forms a small
slope, which is closely beset with zooids (fig. 3, b). The
lateral surfaces are very narrow; and are occupied by
two lancet-formed, somewhat elevated, zooidal areas, which
extend upwards between the polyps; (fig. 2, b) so, that on
each side, there is an area between two polyps, and
another area between a polyp and the dorsal surface. These
poly]) areas become more distinct, and numerous,
according as the development of the animal proceeds, and the
number of polyps increases; and they are no doubt the
same, that Mylius in his description calls; the
lancet-formed leaves of the chalice, and which may be recognised
both in his and Ellis’ illustrations.
The rachis carries five polyps; of these, one forms a
complete terminal polyp which proceeds from the superior
point of the rachis (figs. 2, c. 3, ♂). Of the remaining
four polyps; two proceed from each side, but closer to the
dorsal surface; (figs. 2, d. 3, d) giving rise to a distinct
bilateral symmetry. The body of the terminal polyp is 5"""
long and about 2""" broad and the tentacles are nearly twice as
long. The body of the three lateral polyps, is nearly t’""
long, and 2.5""" broad; but the body of the fourth polyp, is
of the same size as that of the terminal polyp. The
proportion between the tentacles and the body, is the same as
in the terminal polyp. The body of the polyps is
cylin-dric, and smooth, and it has 8 rather broad longitudinal
lines, denoting the insertions for septa. At the base ol’
the terminal polyp; next to the dorsal surface; a small
knob-formed protuberance is observed; this is a polyp
in process of development (fig. 2, e).
The oral disk is arcuate, and in its middle, there is
an oblong oral fissure; furnished with 8, rather thick,
lancet-formed labia?, which, in the middle of the interior
surface, have a furrow.
The axis extends, from the base of the bulbous part,
to the superior extremity of the stalk. In this course; il
occupies the middle of the stalk, up towards the superior,
bent, sheath-formed, dilated part, where, it approaches so
close to the ventral surface; that it appears, as if it passes
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