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der danner den egentlige Stamme og er fremkommen ved
en Sammensmeltning af Endognath og Mesognath, gaar ud
i en smalt tungeformig, i dell indre Kant borstebesat Lap.
uden nogen tydelig Leddeling. Den midterste Gren
(Exog-natli). der aabenbart svarer til den membranøse Plade paa
2det Par Kjæver. er betydelig større og ligesom den indre
fortilrettet, samt bestaar af en noget pladeformig, i den
ydre Kant tæt børstebesat Easaldel og en ganske tynd,
indadkrummet og stærkt bugtet Endesnært, hvis ydre Parti
er delt i korte med Fjærbørster besatte Led. Den ydre
Gren endelig (den saakaldte Epignath) har Formen af en
temmelig stor hudagtig, i to koniske Fliger — en fortil og
en bagtilrettet — udgaaende borstelos Plade.
2det Par Kjævefodder (Fig. 14) viser de samme
Hoveddele som foregaaende Par. skjøndt temmelig modificerede i
sit Udseende. Navnlig er den indre Gren her betydelig
stærkere udviklet, dannende en paa Midten vinkelformigt
bøiet og indadkrummet Stamme, der er afdelt i (i tydelige
Led. Af disse er det næstsidste størst og ligesom opsvulmet
paa Midten samt langs den ydre Kant forsynet med talrige
lange og stive Børster. Sidste Led. der ved en meget skjæv
Sutur er begrændset fra foregaaende, er ganske kort og
bevæbnet med flere ulige store Torner, hvoraf 3 udmærker
sig ved betydelig Længde. Exognathen, der er fæstet til
Ydersiden af Stammens 2det Led, bestaar ligesom paa
foregaaende Par af en noget sammentrykt Basaldel. der er
bredest ved Roden og her i den ydre Kant besat med
lange hoiede Fjærbørster. samt en tynd Endesnært, der er
rettet indad og mindre bugtet end paa lste Par. Epignathen
er ogsaa her tilstede, men er betydelig mindre end paa
foregaaende Par og mangler ganske den fortilrettede Lap.
3die Par Kjævefodder (Fig. 15) skiller sig væsentlig
fra de øvrige Munddele ved sin betydelige Størrelse og
fod-fornhge Bygning. De opnaar næsten hele Rygskjoldets
Længde og rager fortil adskilligt ud over 2det. Par Foleres
Blad. Tilsyneladende bestaar disse Kjævefødders Stamme
kun af 4 Segmenter, et kort og tykt Rodled, et meget
langstrakt og noget bugtet 2det Led, et neppe halvt saa
stort 3die Led og et stærkt affladet, næsten spadeformigt
Endeled. Ved nøiere Undersøgelse finder man dog. at
Rodleddet egentlig er sammensat af 2 ufuldstændigt
begrændsede Segmenter, hvoraf det 2det paa sin Yderside gaar ud
i en kort, tungeformig Flig, der imidlertid neppe, som
Krøyer mener, svarer til Epignathen paa de 2 foregaaende
Par. Fremdeles er der en vistnok svag Antydning til en
Sondring paa næste Led af et kort Basalafsnit, fra hvis
Yderside den i Bygning og Storrelse med samme paa
foregaaende Par nøie overensstemmende Exognath udgaar.
Endelig bemærkes ved stærk Forstørrelse og Compression i
Spidsen af sidste Segment et yderst lidet, men tydeligt afsat
Endeled. Leddenes Antal bliver saaledes egentlig 7. sva-
branch, which constitutes the actual trunk, and results from
a coalescence of the endognath and the mesognath, protends
as a slender, linguiform lobule, beset along the inner margin
with bristles, and does not exhibit any distinct articulation.
The middle branch (exognath). which obviously corresponds
to the membranous plate on the 2nd pair of maxillæ. is
considerably larger, and, like the innermost, directed
anteriorly. consisting, too, of a somewhat lamellar basal portion,
densely beset with bristles along the outer margin, and a
delicate, inwardly curving and exceedingly sinuous terminal
lash, the outer part of which is divided into short
articulations, beset with plumose bristles. Finally, the outermost
branch (the so-called epignath), cutaneous in substance and
without bristles, has the form of a comparatively large
plate, protending into two conical lobes — one directed
anteriorly and one posteriorly.
The 2nd pair of maxillipeds (fig. 14) exhibit the same
principal parts as the foregoing pair, though of
considerably modified appearance. The innermost branch, in
particular, is much more developed, constituting a geniculate
stem, curving inward, and divided into 6 distinct
articulations. Of these articulations, the penultimate is the largest,
and, as it were, tumified in the middle, and furnished along
the outer margin with numerous long and stiff bristles.
The last articulation, which, by an exceedingly oblique
suture, is separated from that preceding it, is very short
and armed with several large spines, varying in length. 3
of.which, however, are remarkably long. The exognath.
attached to the outer margin of the 2nd articulation of the
stem, consists, as does that on the preceding pair, of a
somewhat compressed basal portion, broadest at the root,
and beset along the outer margin with long, curving
plumose bristles, having also a slender terminal lash, directed
inwards, and less sinuous than that on the 1st pair. The
epignath is also present, though much smaller than that on
the preceding pair, the anteriorly directed lobe being
entirely wanting.
The 3rd pair of maxillipeds (fig. 15) are chiefly
distinguished from the other buccal appendages by their considerable
size and pediform structure. They attain almost the entire
length of the carapax. and. in front, project considerably
beyond the scale of the 2nd pair of antennæ. Apparently,
the stem of these maxillipeds consists of only 4 segments,
— a short and thick basal articulation, an exceedingly
elongate and very sinuous 2nd articulation, a 3rd
articulation, scarcely half as large, and an extremely flattened, almost
spatulate, terminal articulation. On closer examination,
however, the basal articulation is found to be composed
of 2 imperfectly separated segments, of which the 2nd
sends off from its outer margin a short, linguiform lappet,
that hardly, however, as assumed by Krøyer, can
correspond to the epignath on the 2 preceding pairs. Moreover,
on the next articulation there is a trace, faint indeed,
of a basal section, from the outer margin of which
proceeds the exognath. precisely similar in size and
structure to that on the preceding pair. Finally, when
examined under a powerful magnifier and highly compressed,
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