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ved Spidsen et Par meget lange og tynde Borster. De 4
torste Led forestiller Skaftet, de 2 sidste Svøben.
Munddelene viser sig. naar Dyret sees nedenfra (se
Fig. 71 sammentrængte paa et forholdsvis lidet Bum og til
Siderne indesluttede af de paa Bugsiden ombøiede Sidedele
af Hovedskjoldet. Fortil mellem Boden af idet Par Følere
bemærkes en liden afrundet firkantet, noget fremspringende
Plade, der forestiller Overlæben. Umiddelbart bag denne
og tildels dækket af samme sees de brunt farvede Tænder
paa Kindbakkernes indre Ender. Den øvrige Del af disse
Organer ligesom Underlæben og Kjæverue dækkes derimod
fordetmeste ganske af Kjævefødderne. Disse viser en
lignende Bygning som hos 81. Sphyrapus. Den 4-leddede Palpe
er noget udadrettet og langs den indre Kant tæt besat med
stærke indadkrummede Børster.
1ste Fodpar (se Fig. 6 og 7) er som hos de øvrige
til denne Tribus hørende Former udviklede til særdeles
kraftige Griberedskaber. De udspringer temmelig nær
sammen med en bred Basis fra den bagerste Del af
Hovedseg-mentets Ventralside og retter sig med en stærk Sformig
Bøi-ning fortil langs Siderne af Hovedskjoldet. Leddene er
særdeles brede, noget sammentrykte fra Siderne og fyldte med
kraftige Muskler; de 2 sidste danner tilsammen en vel
udviklet Sax, der indtager omtrent ’/ä af Fodens Længde.
Fingrene, der neppe er kortere end Palmen, ender med en
skarp, stærkt krummet og hornfarvet Spids og viser langs
den indre Kant nogle uregelmæssige tandformige Fremspring,
der gribe ind mellem hverandre, naar Saxen er lukket isml.
Fig. 14); i dette Tilfælde krydser Spidserne hinanden meget
stærkt.
De øvrige Fodpar (se Fig. 5 og ti) er alle omtrent
af eus Udseende og forestiller de egentlige Gangfødder. De
er af meget spinkel Form, med Basalleddet størst, men
neppe bredere end de øvrige Led. Eudekloen er paa alle
ganske kort og simpel, ligesom de paa disse Fodpar fæstede
Borster er smaa og faa i Antal.
Bagkroppens Buglemmer (se Fig. 8 og 9) er ganske
og aldeles rudimentære og saa smaa, at de meget let kan
forbisees. De er imidlertid tilstede i det sædvanlige Antal
og fæstede nær de afrundede Sidekanter af de 5 forreste
Segmenter (se Fig. 8). De bestaar som sædvanligt af en
Basaldel og 2 Endeplader; men disse sidste er særdeles
smaa og mangler ganske ethvert Spor af Børster, hvorfor
disse Lemmer heller ikke kan fungere som Svømmeredskaber.
hvortil desuden deres ringe Størrelse vilde gjøre dem ganske
utjenlige.
Halevedhængene (se Fig. 8 og 10) er forholdsvis meget
korte, paa langt nær ikke af sidste Segments Længde, og
viser ialmindelighed en skraa Betning indad mod Midtlinien,
saa at, naar Dyret sees ovenfra, oftest kun de lange
Ende-borster rager frem fra Segmentets bagre Band. De bestaar
remarkably small, and not visible save when highly
magnified ; it bears at the point a couple of very long and slender
bristles. The 4 first joints represent the peduncle, the 2
last the flagelluni.
The oral appendages — on viewing the animal from
below (see fig. 7) — appear crowded over a -relatively small
space and enclosed at the sides by the lateral parts of
the cephalic shield, that bend over on the ventral surface.
Anteriorly, between the bases of the 2nd pair of antennæ,
is seen a small, rounded, quadrate, somewhat projecting plate,
representing the labrura. Immediately posterior to this
plate, and partially covered thereby, appear the
brown-coloured teeth, at the inner extremities of the mandibles.
The remaining portion of these organs, as also the labium
aud the maxillæ, are, on the other hand, as a rule, entirely
concealed by the maxillipeds. The latter exhibit a similar
structure to those in the genus Sphyrapus. The four-jointed
palp is directed somewhat outward, and closely beset along
the inner margin with strong incurving bristles.
The 1st pair of legs isee tigs, (i, 7) are. as in the
other forms belonging to this tribe, developed to exceedingly
powerful organs of prey. They have their origin rather
close together, with a broad base, from the posterior part
of the ventral side of the cephalic segment, proceeding
anteriorly. in a strong, S-sliaped curve, along the sides of
the cephalic shield. The joints are exceedingly broad,
somewhat compressed from the sides, and provided with powerful
muscles; the 2 last constitute together a well-developed
chela, measuring about one-third of the length of the leg.
The fingers, scarcely at all shorter than the palm, terminate
in a short, exceedingly curved, and horn-coloured point, and
exhibit, along the inner margin, a few irregular, dentiform
projections, that fit in between one another when the chela
is closed (see fig. 14). the points then crossing very
prominently.
The remaining pairs of legs (see figs. 5. Hi have all
about the same appearance, and represent the true
pereio-poda.. They are exceedingly slender in form, with the
basal joint largest, but scarcely at all broader than the
other joints. The terminal claw is without exception quite
short and simple, the bristles, too, attached to these pairs
of legs being likewise small and few in number.
The abdominal limbs (see tigs. 8, 9) are in every sense
rudimentary, and so small as to be easily overlooked.
Meanwhile, they are present in the usual number, and attached
close to the rounded lateral margins of the 5 anterior
segments of the abdomen (see fig. 8). They consist as usual
of a basal part and 2 terminal plates; but the latter are
exceedingly small, and do not exhibit a trace ol’ bristles;
hence these parts can by no means serve as natatory
organs, for which, too. their small size must render them
wholly inefficient.
The caudal appendages (see figs. 8, 10) are
comparatively very short, not attaining by far the length of the
last segment, and have as a rule an oblique, inward direction
towards the medial line, so that, on viewing the animal
from above, it is generally the terminal bristles alone that
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