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122
Hoveilsegmentet som fra den følgende Del af Truncus;
forøvrigt er ingen tydelig Segmentering paa Kroppen
be-mærkelig. Sidefortsatserne er (se Fig. 1 b) temmelig tykke,
næsten kolledannede, og har ved Enden oventil 2 ens
udviklede pigformige Fortsatser, hver endende med en stiv
Børste. Hovedsegmentet indtager ikke fuldt 1/3 af
Kroppens Længde og er næsten jevnt tykt, uden nogen tydelig
Hals. Dets forreste Parti, eller Pandedelen, er tvært
af-kuttet i Enden, med Sidehjørnerne udtrukne i en konisk
fortilrettet Fortsats, forsynet med en liden Børste i Spidsen
(se Fig. 1 e). De 2 bagerste Kropssegmenter er
fuldstændig sammenvoxne og kun antydede ved de fra dem
udgaaende Sidefortsatser, hvoraf det sidste Par som
sædvanlig er kortere og mere bagudrettet. Halesegmentet,
der heller ikke er tydeligt afgrændset fra Kroppen, er
meget smalt, cylindriskt, og af betydelig Længde, omtrent
som Hovedsegmentet, samt horizontalt, endende i en stump
Spids.
Øieknuden (se Fig. 1 b. 1 c. 1 e), der er beliggende
helt fortil, nær Enden af Pandetlelen, er af betydelig
Størrelse og stærkt ophoiet. Den er noget forover rettet og
af cylindrisk Form, med et ganske kort kegleformigt
Fremspring i Midten af den stumpt afrundede Ende. Lindserne
er forholdsvis smaa og beliggende helt ved Toppen af
Øieknuden.
Snabelen (se Fig. 1 b. 1 c. 1 d) udgaar noget ventralt
fra Hovedsegmentets Ende og er meget skarpt afgrændset
fra samme, idet der omkring dens Basis findes en fortykket
circulær Kant (se Fig. 1 d), hvorved paa en Maade en
Slags Ledforbindelse kommer istand. Den er af betydelig
Størrelse, over halvt saa lang som det øvrige Legeme, og
ialmindelighed mere eller mindre skraat nedadrettet. Af
Fonn er den udpræget tendannet, idet den ved Basis har
en stærk Indknibning og successivt udvides til henimod
Midten, hvorfra den igjen hurtigt afsmalnes mod Enden,
som er stumpt tilspidset. Som hos andre Pycnogonideer
er den sammensat af o Længdesegmenter, hvoraf det
uparrede og smaleste indtager Dorsalsiden, de 2 øvrige en Del
af Sidefladerne og hele Undersiden, hvor de støder sammen
langs efter Midten (se Fig. 1 d). Mellem Segmenterne
tindes tætte tværgaaende Muskler, der især i det basale
Parti af Snabelen er tydelige. Mundaabningen, der ligger
paa Spidsen, er begrændset af 3 tydeligt fremspringende
Læber.
Saxlenmierne er hos det voxne Dyr (se Fig. 1 b. I c)
yderlig smaa og rudimentære, neppe længere end Øieknuden
er høi, og fæstede temmelig nær sammen til den forreste
Rand af Hovedsegmentet ovenover Snabelens Basis. Skaftet
er (se Fig. 1 f) af kolledannet Fonn og gaar ved Enden
oventil ud i en temmelig stærkt fremspringende, i Spidsen
tvekloftet Fortsats besat med 2 pigformige Borster.
Ende-partiet, der svarer til Haanden hos andre Pycnogonideer,
har kun Formen af et lidet kugleformigt Led, uden nogen
Antydning til Fingre. Ved stærk Forstørrelse kan dog
tinctly demarcated, both from the cephalic segment as
well as the succeeding portion of the trunk; there is,
otherwise, no distinct segmentation to be noticed on the
body. The lateral processes (s’ee fig. 1 b) are pretty thick,
almost clavate, and have at the extremity above 2 equally
developed spiniform processes, each terminating in a stiff
bristle. The cephalic segment occupies not quite 1 of
the length of the body and is almost uniform in
thickness, without any distinct neck. Its anterior portion, or
the frontal part, is truncated at the extremity, with the
lateral corners drawn out to a conical process, directed
forwards and furnished with a small bristle at the point
(see fig. 1 e). The 2 posterior segments of the the trunk
are completely coalesced and only indicated by the lateral
processes that issue from them, of which the last pair is,
as usual, shorter and more posteriorly directed. The caudal
segment, which, also, is not distinctly demarcated from
the trunk, is very narrow, cylindric, and of considerable
length, about the same as the cephalic segment, horizontal,
and terminates in a blunt point.
The ocular tubercle (see fig. 1 b, 1 c, 1 e), which
is situated quite in front, near the end of the frontal
part, is of considerable size and strongly protuberant. It
is directed forwards a little and is cylindric in form, with
a quite short conical prominence in the middle of the
bluntly rounded extremity. The lenses are relatively small,
and situated quite at the top of the tubercle.
The proboscis (see fig. I b. 1 c. 1 d) issues
somewhat ventrally from the end of the cephalic segment, and
is very distinctly demarcated from it, as round its base
there occurs a thickened circular edge (see fig. 1 d) by
which there is, in a manner, formed a kind of articulatory
connection. It is of considerable, size, more than half
as long again as the rest of the body, and, usually, is more
or less directed obliquely downwards. In shape it is
distinguished fusiform, as at its base it has a strong
constriction and is progressively expanded towards the middle,
whence it again rapidly diminishes towards the extremity,
which is bluntly painted. As in other Pycnogonids it is
composed of 3 longitudinal segments, of which the
unpaired and narrowest occupies the dorsal side, the 2 others
a portion of the lateral surfaces and the entire under side
where they unite along the middle (se fig. 1 d). Between
the segments closely placed transversal muscles are found,
which are especially distinct in the basal portion of the
proboscis. The oral aperture, which is situated at the
point, is bordered by 3 distinct protruding lips.
The chelifori are, in the adult animal (see fig. 1 b.
1 c), extremely small and radimentary, scarcely longer
than the ocular tubercle is high, and are secured pretty
closely together to the foremost margin of the cephalic
segment above the base of the proboscis. The scape is
(see fig. 1 t) clavate in form and at the extremity, above,
passes into a pretty strongly prominent process,
bifurcated at the point and beset with 2 spiniform bristles.
The terminal part, which corresponds to the hand in other
Pycnogonids, has only the form of a small globular joint,
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