ae 
afrundede Endeled er meget reducerede i Antal. Epi- 
poditen er overmaade liden og rudimenteer, hvorimod 
Exopoditen er forholdsvis vel udviklet, naaende med 
sin ventrale Lap langt ud over Endopoditen. Den 
er kantet med omtrent 23 Borster af noget ulige 
Lengde. Meget lignende, skjondt endnu noget sim- 
plere, er Bygningen af det 24de Par hos meget store 
Exemplarer, saaledes som dette er beskrevet og af- 
bildet af Prof. Lilljeborg. 
Legemets Farve er hos fuldvoxne Exemplarer 
mere eller mindre tydelig olivengron, gaaende paa 
Bugsiden og paa Fodderne over til gulrodt. Selve 
Skallen er lyst hornfarvet og temmelig gjennem- 
sigtig, dog meget constant med Dorsalkanten af en 
ret ioinefaldende mork graasort Farve. 
Indre Organer. 
Paa Grund af denne Forms store Gjennemsigtig- 
hed, vil den indre Organisation ret vel kunne stu- 
deres, navnlig paa levende Exemplarer, tildels ogsaa 
paa vel preserverede Spiritusexemplarer, uden at 
nogen Dissection strengt taget er fornoden. Kun 
hvor det gjelder en mere detailleret (histologisk) 
Undersogelse af Organerne, vil det vere nyttigt at 
skride til en Sonderlemmelse af Dyret. 
Med den seedvanlige Indleirings- og Snitmethode 
kommer man ikke synderlig vidt, og denne i vor 
Tid i saa stor Udstrekning anvendte Undersogelses- 
methode synes idethele at vere lidet anvendelig, 
hvor det gjelder Krebsdyr. 
Fordgielsesapparat. — Tarmen strekker sig som 
et nogenlunde jevnt tykt Ror gjennem hele Dyrets 
Legeme, og skinner meget tydeligt igjennem Inte- 
gumenterne ved dens sedvanligvis morke Contenta 
(se Tab. XV, Fig. 1). Den ender i Halen med en 
kort, sterkt muskulos Endetarm, som udmunder paa 
Halens Spids, mellem Haleklorne. I Nakkesegmentet 
gjor Tarmen en pludselig, nesten vinkelformig Boi- 
ning nedad, i Overensstemmelse med Legemets steerke 
Krumning paa dette Sted. Tarmens Indhold er i 
denne forreste Del seedvanligvis lysere, orangefarvet 
eller blegt gulagtigt. Spiseroret er ganske kort og 
passerer fra Mundaabningen lige fortil, hvor det 
munder i Tarmens forreste Ende med en i dens 
Lumen fremspringende noget udvidet Del (se Fig. 9, 
oes). I Forbindelse med Tarmen staar et temmelig 
voluminost og compliceret kjertelagtigt Organ (Fig. 
2, 3, 2), der udfylder en stor Del af Hovedets indre 
Hule, og aabenbart svarer til den hos Lepidurus 
ligeledes i Hovedet beliggende Lever. Ligesom hos 
Lepidurus, bestaar Organet af 2 symetriske Haly- 
from the others. It is very small, and its endopo- 
dite is quite short, with only 3 lobes inside in addi- 
tion to the coxal lobe. The bristles on these lobes, 
as also on the short rounded terminal joint, are 
greatly reduced in number. The epipodite is excee- 
dingly small and rudimentary, whereas the exopo- 
dite is comparatively well developed, reaching far 
out over the endopodite with its ventral lobe. It 
is edged with about 23 bristles of somewhat unequal 
length. The structure of the 24th pair found in 
very large specimens, though rather more simple, 
‘is very similar, as described and figured by Prof. 
Lilljeborg. 
The colour of the body in full-grown specimens 
is more or less distinctly olive-green, merging into 
yellowish red on the ventral side and on the legs. 
The shell itself is of a light horn-colour, and toler- 
ably transparent, though the dorsal margin is 
almost invariably of a very conspicuously dark 
grey colour. 
Internal Organs. 
On account of the great transparency of this 
form, its internal organisation may be very easily 
studied, especially in living specimens, to a certain 
extent too, in well-preserved spirit specimens, with- 
out the necessity of dissection. Only when a more 
minute (histological) investigation of the organs is 
to be made, will it be useful to resort to a dismem- 
bering of the animal. 
By the ordinary imbedding and section method, 
not much information is to be gained, and this mode 
of investigation, now so widely employed, seems, 
on the whole, to be of very little use as regards 
Crustaceans. 
Digestive System.— The intestine runs, in the 
form of a tube of fairly even thickness, through the 
whole body of the animal, and is very distinctly 
seen through the integuments by reason of its gene- 
rally dark contents (see Pl. XV, fig. 1). It -termi- 
nates in the tail in a short, very muscular rectum, 
which opens out at the point of the tail, between 
the caudal claws. In the cervical segment, the inte- 
stine makes a sudden, almost angular bend down- 
wards, following the sharp curve of the body at 
that place.. The contents of the intestine in this 
foremost part. are generally lighter, of an orange 
or pale yellow hue. The csophagus is quite short 
and passes from the oral aperture straight for- 
wards, where it opens into the anterior end of the 
intestine by a somewhat expanded part projecting 
into its lumen (see fig. 9, oes). In connection with 
the intestine, there is a rather voluminous and 
eomplicated glandular organ (figs. 2, 3, 2) occupying 
a great part of the inner cavity of the head, and 
evidently answering to the liver in Lepidurus, which 
