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41
Led og retter sig lige fortil, er af en meget smal. lineær
Form og i Enden utydeligt leddet og borstebesat;
Epigna-then er af samme Beskaffenhed som paa foregaaende Par.
men af næsten cirkelrund Form. Bag denne udgaar fra
Roddelens ydre Side en smal tungeformig Flig. som ogsaa
forefindes paa det folgende Par samt paa samtlige Fodder.
3die Par Kjævefodder (Fig. 16) er stærkt forlængede,
fodformige og rækker fortilstrakte omtrent til Spidsen af
2det Par Foleres Blad. Af Stammens 5 Led er det 3die
størst og mindre skarpt adskilt fra det foregaaende, samt
temmelig stærkt krummet. Sidste Led er ikke meget kortere,
men stærkt afsmalnende mod Enden, der er udtrukken i
en sylformig Spids. Det er ligesom de foregaaende Led
besat med tætte Borsteknipper, som navnlig i den indre
Kant er stærkt udviklede, hvorimod egentlige Torner mangler.
Til Ydersiden af Stammens 2det Led er fæstet en
vel udviklet Exognath. paa hvilken kan adskilles en smalt
cylindrisk Basaldel og en noget sammentrykt, mangeleddet
og med lange Fjærbørster besat Endedel. Den hele
Exo-gnaths Længde er lige udstrakt omtrent ’/s af Stammens
Længde.
Endelig er til Y’dersiden af Stammens Rodled fæstet
en oval eller elliptisk Epignath. der i høi Grad udmærker
sig derved, at den har antaget Beskaffenheden af en virkelig
Gjelle, idet der fra dens ydre Flade har hævet sig 8—9
tydelige bladformige Tværfolder.
Samtlige Fødder har fæstet til Ydersiden af 2det Led
eu vel udviklet Svømmegren (Exopodit) ligesom hos
Schi-zopoderne og svarende til den saakaldte Exognath paa
Munddelene.
De to forreste Par er kortest og som bos Pasiphae
forsynede med Saxe; de 3 bageste Par er derimod simple i
Enden.
1ste Fodpar (Fig. 17) er knapt saa langt som sidste
Par Kjævefodder og af forholdsvis svag Bygning. Af
Leddene er det 4de størst og længere end de 3 foregaaende
tilsammen. 5te Led danner med dette i Regelen en stærk
knæformig Boining og er knapt ’/3 saa langt. 6te Led
eller Haanden er kun lidet tykkere end det foregaaende
Led og indtager omtrent ’/’i af Fodens Længde. Fingrene
er, sammenlignet med samme hos Pasiphae, meget korte,
neppe halvt saa lange som Palmen, temmelig tynde og i
Spidsen svagt krummede (se ogsaa Fig. 18). Alle Led er
mere eller mindre tæt børstebesatte, navnlig i den indre
Kant; dog er Børsterne paa selve Haanden meget korte.
Svommegrenen er stærkt udviklet og rækker lige
for-tilstrakt ud over 4de Led. Dens Bygning stemmer
forøvrigt fuldkommen overens med Exognathen paa sidste Par
Kjævefodder.
Dell norske Nordliavsexpeditoin. G. O. Sars: Crustacea.
The exognath. attached to the outer side of the 2nd joint
of the stem and protending straight forward, has an
exceedingly slender, linear form, and at the end is
indistinctly articulated, and beset with bristles; the epignath
exhibits a structure similar to that in the preceding pair, but
a well-nigh circular form. Posterior to the latter, proceed
from the outer side of the basal part a narrow, linguiform
lobule, which also occurs on the succeeding pair, and on
all of the legs.
The 3rd pair of maxillipeds (fig. 16) are greatly
produced. pediform, and reach, extended anteriorly, about
to the point of the scale of the 2nd pair of antennæ. Of
the 5 joints of the stem, the 3rd is the largest, and less
distinctly separated from the preceding, as also a good deal
curved. The terminal joint is not much shorter, tapers
rapidly toward the extremity, which is drawn out to an
awl-shaped point. Like the preceding joints, it is beset
with dense fascicles of bristles, which, more particularly
on the inner margin, are strongly developed; true spines,
however, do not occur.
To the outer side of the 2nd joint of the stem is
attached a well-developed exognath, on which can be
distinguished a narrow, cylindric basal portion and a somewhat
compressed, multiarticulate terminal part, beset with long,
plumose bristles. The whole length of the exognath, when
fully extended, equals about one-third of the length of the
stem.
Finally, on the outer side of the basal joint of the
stem is attached an oval or elliptic epignath, strikingly
distinguished by having assumed the character of a true
branchia, 8 or 9 distinct transverse folds rising from its
outer surface.
All of the legs have a well-developed natatory branch
(exopodite) attached to the outer side of the 2nd joint, as
in the Schizopods. corresponding to the so-called exognath
on the oral appendages.
The two anterior pairs are shortest, and. as in Pasiphae.
furnished with chelæ; the three posterior pairs are, on the
other hand, simple at the extremity.
The 1st pair of legs (fig. 17) are scarcely as long as
the last pair of maxillipeds, and comparatively feeble in
structure. Of the joints, the 4th is the largest, and longer
than the three preceding ones taken together. The 5th
joint forms along with the 4th. as a rule, a strong, geniculate
bend, and is hardly one-third as long as the latter. The 6th
joint, or hand, is but little thicker than the preceding joint,
and measures about one-fourth of the length of the leg.
The fingers, as compared with those in Pasiphae, are
exceedingly short, scarcely half as long as the palm, somewhat
slender, and at the point sbghtly curved (see. too, fig. 18).
All of the joints are more or less densely beset with bristles,
in particular along the inner margin; the bristles on the
hand itself, however, are very short.
The natatory branch is powerfully developed, and
reaches, anteriorly extended, beyond the 4th joint. For
the rest, its structure perfectly agrees with that of the
exognath on the last pair of maxillipeds.
6
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