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168
Af Lemmer rindes hos Hunnen kun de 4 Par
Gang-fødder. Hertil kommer imidlertid hos Hannen et 5te Par,
fra Bugsiden af Hovedsegnientet udgaaende Lemmer, de
saakaldte falske Fodder (se Fig. 1 f). Derimod er der hos
fuldt udviklede Dyr intetsomhelst Spor hverken af
Saxlemmer eller Folere at opdage.
Gangfødderne (Fig. 1 c) er af temmelig plump og
kraftig Bygning, noget kortere end Legemet og bestaaende
af det sædvanlige Antal (8) Led. Af de 3 Hofteled er
det lste størst og temmelig bredt, især paa sidste Fodpar
(se Fig. 1), hvor det ligger tæt ind mod Halesegmentet,
der herved viser sig ligesom indkilet mellem Basis af dette
Fodpar. Laarleddet er omtrent saa langt som de 2 sidste
Hofteled tilsammen og af en noget uregelmæssig Fonn,
med den indre Kant vinkelformigt udbuet paa Midten og
den ydre eller øvre Kant gaaende ud ved Enden af
Leddet i 2 jevnsides stillede, mere eller mindre tydelige koniske
Fremspring. lste Lægled er lidt kortere end Laarleddet,
stærkt indknebet ved Roden og gaar ved Enden paa den
øvre Side ud i 2 lignende, men noget mindre Fremspring.
2det Lægled er betydelig mindre, noget skraat afskaaret i
Enden og viser Antydning til lignende Fremspring som
paa de 2 foregaaende Led. Tarsalleddet (se ogsaa Fig.
1 d) er meget kort, af trekantet Form og paa Ydersiden
næsten ganske dækket af foregaaende Led; dets indre Kant
er bueformigt bøiet og, ligesom en Del af foregaaende Leds
Inderkant, tæt besat med korte, tornformige Borster.
Fodleddet er mere end 3 Gange længere end Tarsalleddet,
men betydelig smalere, temmelig stærkt krummet og
overalt omtrent af ens Brede. Inderkanten er noget concav
og tæt besat, med lignende korte Borter som paa
Tarsalleddet og ender med en liden smalt afrundet Lap.
Endekloen er særdeles kraftig, mere end halvt saa lang som
Fodleddet og af hornbrun, ofte næsten sort Farve. Den
er i sit ydre Parti jevnt krummet og ender med en
syl-skarp Spids. Af Bikloer er der ikke det mindste Spor at
opdage.
De falske Fødder findes, som anfort, alene hos
Hannerne, og deres Function synes her udelukkende kun at
være den at fastholde den ydre Ægmasse. De er (se Fig.
1 f) fæstede til hver Side under den forreste Del af
Hovedsegmentet til et lidet afrundet Fremspring, og er i
Sammenligning med samme hos andre Pycnogonideer meget
smaa og svage, idet de knapt opnaar ’/4 af Legemets
Længde. Ved nøiere Undersøgelse (Fig. 1 g) viser de sig
at bestaa af det samme Antal Led som Gangfodderne og
ender som disse med en kraftig Klo; men Længdeforholdet
mellem Leddene er meget forskjelligt. De 4 förste Led er
forholdsvis meget smaa og næsten af ens Længde,
hvorimod de følgende 4 er noget storre, navnlig 5te og 6te.
Langs den indre Kant af Leddene bemærkes nogle meget
smaa og uregelmæssigt fordelte Torner af ganske simpel
Fonn (Fig. 1 h). Endekloen er omtrent saa lang som det
usual triangular form, though wanting distinctly developed
lip-plates.
Of limbs, occur in the female only the 4 pairs of
ambulatory legs. The male however is furnished with a 5th
pair, the so-called false legs (see fig. 1 f), issuing from the
ventral side of the cephalic segment. On the other hand,
in fully developed animals no trace cail be detected of
either chelifori or palps.
The ambulatory legs (fig. 1 c) are rather clumsy and
powerful in structure, somewhat shorter than the body,
and composed of the usual number (8) of joints. Of the
3 coxal joints, the first is the largest, and rather broad,
more especially on the last pair of legs (see fig. 1), where
it lies close up to the caudal segment, which has thus the
appearance of being wedged in between the base of this
pair of legs. The femoral joint is about as long as the 2
last coxal joints taken together and of a somewhat
irregular form, witli the inner margin bent out angularly in the
middle and the outer or upper margin running at the
extremity of the joint into 2 parallel, more or less distinctly
conic projections. The 1st tibia® joint is a trifle shorter
than the femoral, very considerably instricted at the base,
and divides at the extremity on the upper side into 2
similar, but somewhat smaller projections. The 2nd tibial
joint is a good deal smaller, cut off somewhat obliquely at
the extremity, and indicates the occurrence of similar
projections, as ill the 2 preceding joints. The tarsus (see fig.
1 d) is very short, triangular in form, and on the outer side
well-nigh wholly covered by the preceding joint; its inner
margin is arched and, as with part of the inner margin of
preceding joint, densely beset with short spiculiform bristles.
The propodus has more than 3 times the length of the
tarsus, but is considerably narrower, very much curved, and
everywhere of well-nigh the same breadth. The inner margin
is a little concave, densely beset with short bristles similar
to those on the tarsus, and terminates in a small, narrowly
rounded lobe. The terminal claw is remarkably powerful,
more than half as long as the tarsus, and of a horny
brown, often well-nigh black colour. It has the outer part
uniformly curved and terminates in a sharp point. Of
auxiliary claws not a trace can be detected.
The false feet occur, as stated above, in the males
only; and their function would seem to lie exclusively that,
of grasping the outer egg-mass. They are affixed (see
fig. 1 f) on either side, under the foremost part of the
cephalic segment, to a small rounded projection,, and are,
as compared with those limbs in other Pycnogonids, very
small and feeble, attaining scarcely one-fourth of the length
of the body. On closer examination (fig. 1 g), they are
found to have the same number of joints as the
ambulatory legs, and, like those limbs, they terminate in a powerful
claw; but as to length, the proportion between the joints is
rather different. The 4 first joints are comparatively very
small and almost equal in length, whereas the following
4 are somewhat larger, in particular the 5th and 6th.
Along the inner margin of the joints extend a few very
small and irregularly distributed spines of quite a simple
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