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130
delig store, kjendelig længere end Kroppen er bred, og
kun adskilte ved smale Mellemrum. De er noget
fortykkede i Enden og langs Kanterne fint haarede.
Hovedsegmentet er omtrent saa langt som de 3 følgende Segmenter
tilsammen og afsmalnes kjendeligt fortil, idet Pandedelen
kun er meget svagt udvidet. I nogen Afstand fra de
forreste Sidefortsatser udgaar fra Halsdelen til hver Side et
temmelig stort, smalt afrundet Fremspring, hvortil de falske
Fødder er indleddede. Halesegmentet (Fig. 1 g) er, uligt
hvad Tilfældet er hos de fleste øvrige Pycnogonideer, meget
skarpt afsat fra sidste Kropssegment, med hvilket det synes
at være bevægeligt artieuleret. Det er forholdsvis smalt,
men af betydelig Længde, omtrent ligt de 3 bagerste
Krops-segmenter tilsammen, og horizontalt bagudrettet. Af Form
er det smalt tendannet, stærkt indknebet ved Basis og
successivt udvidet til bag Midten, hvor det danner en noget
vinkelformig Boining; det er her forsynet med en Tværrad
af 4—<5 stærke, divergerende Borster, hvoraf de 2 staar
tæt sammen paa Rygsiden. Denne Tværrad af Børster i
Forbindelse med den eiendommelige Boining paa dette Sted
giver ved første Øiekast Indtrykket af en Segmentering,
og Kröyer har ogsaa feilagtigt beskrevet Halesegmentet
som bestaaende af 2 Led.
Øieknuden (se Fig. 1 b, t c), der bar sin Plads lidt
foran Midten af Hovedseginentet, er stærkt ophøiet, noget
foroverrettet, og af meget smal cylindrisk Form. Toppen
er noget fortykket og ender i en stump Spids samt har
til hver Side et lidet tandformigt Fremspring. Lindserne
er vel udviklede, af middels Størrelse, og beliggende lige
ved Enden af Øieknuden.
Snabelen (Fig. 1 d) er af en meget eiendommelig
Bygning. Den bestaar nemlig af to skarpt afsatte og med
hinanden bevægeligt forbundne Dele, et smalt cylindriskt,
lige fortilrettet Skaft, omtrent af Hovedsegmentets halve
Længde, og et stærkt opsvulmet, tentormigt Endeparti, der
ialniindelighed er bøiet ind under Kroppen. Naar begge
Dele er udstrakte i samme Plan (se Fig. 1 a) er Snabelens
Længde omtrent lig de 4 egentlige Kropssegmenter
tilsammen. Af de to ovennævnte Dele er det egentlig
kun Endepartiet, der svarer til Snabeleu hos andre
Pycnogonideer.
Saxlemmerne (Fig. t e) maa vistnok, som. hos de til
foregaaende Familie borende Former, siges at være
rudimentære, forsaavidt som de hos fuldt udviklede Individer
mangler en egentlig Chela, men de er dog af ikke
ubetydelig Længde, idet de er mere end halvt saa lange som
Legemet. De er forholdsvis meget smale, næsten lige
fortilstrakte, og bestaar af 3 tydeligt begrændsede Led.
Af disse tilhorer de 2 første [aabenbart Skaftet, som
saaledes, afvigende fra hvad Tilfældet pleier at være’ hos
Pycnogonideerne, er 2-leddet. 1ste Led er noget kortere
og betydelig tykkere end 2det, der er af smal lineær
Form; begge er paa den øvre Side forsynede med stærke,
are . unusually large, appreciably longer than the trunk is
broad, and are only separated by narrow intervals. They
are somewhat tumeficated at the extremity and finely setous
along tile margins. The cephalic segment is about as
long as the 3 succeeding segments taken together, and
tapers appreciably in front, as the frontal part is only
very faintly expanded. At some distance from the
foremost lateral processes, a pretty large, narrow, rounded
prominence, to which the false legs are articulated, issues
on each side from the cervical part. The’ caudal segment
(fig. 1 g). is. unlike the case in other Pycnogonids, very
sharply demarcated from the last segment of the trunk,
with which it seems to be flexibly articulated. It is
relatively narrow but of considerable length, about ecpial
to the 3 posterior segments of the trunk taken together,
and is directed horizontally backwards. In shape it is
narrow fusiform, strongly constricted at the base and
successively expanded till behind the middle, where it
forms a somewhat angular bend: it is here furnished with
a transversal series of 4—G strong, divergent bristles, of
which 2 stand close together on the dorsal side. This
transversal series of bristles in conjunction with the peculiar
bend at this part gives, at the first glance, the impression
of a segmentation, and Kröyer has also erroneously described
the caudal segment as consisting of 2 joints.
The ocular tubercle (see fig. 1 b, 1 c), which is
situated a little in front of the middle of the cephalic
segment, is strongly protuberant, directed somewhat forward,
and very narrow cylindrie in form. The top is somewhat
tumeficated and terminates in a blunt point, and on each
side has a small dentiform prominence. The lenses are
well developed, of medium size, and are situated quite at
the extremity of file ocular tubercle.
The proboscis (fig. 1 d) is very peculiar in structure.
It consists, namely, of 2 sharply defined parts flexibly
connected to each other, a narrow, cylindrical scape
directed straight forward, about half the length of the
cephalic segment, and a strongly swollen, fusiform
terminal part, which is usually folded in under the trunk.
When both portions are extended in the same plane (see
fig. 1 a) the length of the proboscis is about equal to
that of the 4 segments proper of the trunk, taken together.
Of the 2 above-named portions, it is really only the
terminal part that corresponds to the proboscis in other
Pycnogonids.
The chelifori (fig. 1 e) must certainly, as in the forms
pertaining to the preceding families, be said to be
rudimentary, in so far that they in fully developed individuals
have no real chela, but, still, they are of no
inconsiderable |length as they are more than half as long as the
body. They are relatively very narrow, extended almost
straight forward, and consist of 3 distinctly demarcated
joints. Of these the 2 first evidently pertain to the scape,
which thus, differing from what is usually the case in the
Pycnogonids, is 2-jointed. The 1st joint is somewhat shorter
and considerably thicker than the 2nd, which is narrow
linear in form; both are furnished on the upper side with
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