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10
gerste Ende er konisk tilspidset, Fig. 21, b. Den forreste
Del bliver noget smalere, idet den gaar over i Snabelen.
Snabelen er cylindrisk, omtrent 64""" lang, bmm tyk
i dens Begyndelse, Fig. 21, c; men udvider sig
efterhaanden lidt, saa at den op imod den forreste Ende bliver
indtil 9°"", Fig. 21, d; her bliver den i en Afstand af 3—4ram
fra Tentakelkraven noget smalere, danner en Slags Hals,
Fig. 21, e, og ender i en temmelig bred. hvælvet,
actinie-lignende Skive, Fig. 21, /, i hvis Midte findes den runde
Mundaabning, Fig. 21, 22, b, og hvis Omkreds indtages
for Størstedelen af Tentaklerne, Fig. 21, g, 22, c.
Tentaklerne indtage en særegen Stilling paa
Mundskiven. idet den egentlige Tentakelkrave er meget stærkt
bugtet, saaledes nemlig, at den danner 10 store
Indbugt-ninger (Festons) og 10 smaa, Fig. 22. 23.
• De store Indbugtninger strække sig et langt Stykke
ind paa Mundskiven. Enhver saadan Feston er paa dens
to Rande besat med Tentakler, 8. paa hver Rand, Fig. 22,
23, a, og faar derved et fryndset Udseende. De 4 inderste
Tentakler ere de største, derefter aftage de betydeligt i
Størrelse, saa at de to yderste ere temmelig smaa, og faa
Udseende af at gaa over paa den lille Indbugtnings Rand,
naar Tentakelkrandsen ikke er fuldt udstrakt, Fig. 23.
De 10 smaa Indbugtninger ere egentlig Fortsættelser
af de store; men strække sig kun lidt indenfor
Mundskivens Rand, og ere kun forsynede med hver sine to
Tentakler, Fig. 23, b, der ere i Størrelse som de 5te
(indenfra) paa de store Festons.
Alle Tentaklerne ere flade, konisk tilspidsede, og have
paa den ene Flade ligesom en Fure, der fremkommer
derved, at Randene bøie sig lidt imod hinanden. Der er
altsaa ialt 180 Tentakler.
Analaabningen er rund og findes i Centrum af en
temmelig fremstaaende Papille paa Rygsiden, omtrent I0mm
fra Snabelens Grund, Fig. 21, h.
Kroppens Overflade er forsynet med fine Tværlinier,
der blive tydeligere paa Snabelen, Fig. 21, og paa disse
Linier iagttages yderst smaa Papiller, der især paa den
forreste Del af Snabelen staa i temmelig regelmæssige
Grupper, Fig. 22, d, 24. Tydeligst ere dog disse Papiller
paa den bagerste Kropsende.
Huden er meget fast, læderagtig, tyk og stærkt
contractu. Den bestaar af en tyk, gjennemsigtig, glasklar
Cuticula, der er stribet baade efter Længden og Bredden,
Fig. 25, a, 26, a. Paa den ydre Flade af Cuticula
iagttages en stor Mængde fine Porer, Fig. 25, b, 26. 6, der
ere Aabninger for Slimkjettlernes Udførselsgange.
Indenfor Cuticula er den egentlige Matrix, bestaaende
af Epithel- og Pigmentceller, Fig. 25, c, 26, c, og i dette
Lag er en stor Mængde Slimkjertler leirede, Fig. 25, d.
Disse have en konisk Form med en temmelig bred
Grunddel, Fig. 26, d, og fra hvis noget afstumpede Spids, Fig.
Posterior extremity acuminate, fig. 21, b. The anterior
part diminishes sorrtewhat in circumference where it is
produced into the proboscis.
The proboscis is cylindrical in form, about 64mm long,
and 5mm thick at origin, fig. 21, c, but gradually expands
to 9mrn, near the anterior extremity, fig. 21, d; here, 3 or
4 mm from the tentacular collar, it becomes a trifle slenderer,
constituting a kind of neck, fig. 21, e, and terminates in a
comparatively broad, arcuate disk, somewhat like the oral
disk of an Actinia, fig. 21,/, in the middle of which is
the round buccal aperture, figs. 21; 22, b, the greater
part of the peripheral margin being taken up by the
tentacles, figs. 21, g; 22, c.
The position of the tentacles on the buccal disk is
peculiar, the collar itself being remarkably waved, forming
as it does a series of undulations, 10 long (festoons) and
10 short, figs. 22; 23.
The long undulations extend far out on the buccal
disk. Each of these festoons is studded along its two
margins with tentacles, 3 on either margin, figs. 22; 23, a,
which gives them a fringed appearance. The 4 innermost
tentacles are the largest; the others diminish considerably
in size, the two outermost being comparatively small, and
when the whole assemblage forming the collar are not fully
exserted, seemingly placed on the margin of the nearest
short undulation, fig. 23.
The 10 short undulations are strictly continuations
of the large ones, but reaching very little within the
margin of the oral disk, and furnished with only two tentacles
each, fig. 23, b, in magnitude equal to the fifth (counting
from within) of those forming the festoons.
All of the tentacles are flat, acuminate; and the
margins slightly inclining towards each other, a grooved
depression extends along one of the surfaces. Total
number of tentacles 180. ’
The anal opening is round, and placed in the centre
of a rather prominent papilla on the dorsal side, about
10mm from the base of the proboscis, fig. 21, h.
• The surface of the body is transversely striate, the
fine striæ being most conspicuous on the proboscis, fig. 21;
and, dispersed along them, extend a multitude of
exceedingly minute papillæ, which, more especially on the anterior
part of the proboscis, are arranged in comparatively
regular groups, figs. 22, d; 24; the papillæ are most conspicr
uous, however, on the posterior extremity of the trunk.
The skin is exceedingly firm, coriaceous, thick, and
highly contractile. It consists of a thick, hyaline,
translucent cuticle, transversely and longitudinally striate, figs.
25, a; 26, a. On the outer surface of the cuticle, are seen
a multitude of minute pores, figs. 25, b; 26, b, — openings
for the excretory canals of the mucous glands.
Underneath the cuticle, extends the true matrix,
consisting of the epithelium and pigmentary cells, figs. 25, c;
26, c. Throughout this layer are disposed numbers of
mucous glands, fig. 25, d, conical in form, with a
comparatively broad base, fig. 26, d, and a somewhat obtuse sum-
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