29 
Segmenter, og Halegrenene er tydeligt afsatte samt 
hver i Spidsen forsynet med en kort Borste. Pande- 
pladen (R) er nu tydeligt fremragende, og Gienstil- 
kene (O) har antaget en noget konisk Form samt 
viser i sin ydre Del den forste svage Antydning til 
Dannelse af Synselementer. Til hver Side af Tar- 
men bemerkes i Midtkroppen en temmelig plump 
og kort eylindrisk Sek, der aabenbart forestiller en 
af Leverseekkene. Den dorsale Del af Forkroppen 
er endnu sterkt opblest og fyldt af redgul Blomme- 
masse. Umiddelbart nedenfor denne Del sees nu 
tydeligt de frie Kanter af Rygskjoldet. De Foran- 
dringer, Embryonet endnu har at gjennemgaa, er 
ganske successive. Den tilbageverende Rest af 
Blommemassen opbruges lidt efter lidt, og samtidigt 
aftager den dorsale Opsvulning af Hovedet i Stor- 
relse, medens Rygskjoldets Valvler mere og mere 
voxer ud over Siderne af Midtkroppen. De forskjel- 
lige Kropsvedheng udformes og indtager den for 
dem characteristiske Stilling i Forhold til Legemet, 
hvorved ogsaa meget snart Nebalia-Habitusen bliver 
fremtredende. Fig. 12 fremstiller Ungen, naar den 
er ferdig til at forlade Klekkehulen. Man har 
ingensomhelst Vanskelighed med i den at erkjende 
en ung Nebalia. Den eneste vesentlige Afvigelse 
er, at der fremdeles kun er 3 Par Svommefodder 
tilstede. Af det 4de Par sees kun et ubetydeligt 
Anleg bag de ovrige, i Form af et Par smaa knude- 
formige Fremspring (p'). Ungen kan nu bevege sig 
frit i Vandet og ernere sig selv; men det varer 
endnu adskillig Tid, inden de forskjellige Vedheng 
-opnaar sin fulde Udvikling og faar sin normale rige- 
lige Borstebeseetning. Af alle Vedheng er 4de Par 
Svemmefedder de, som udvikler sig senest. 
appendages of the body are all freely projectant, 
while, also, the segmentation of the body is distinct 
externally. The dorsal curvature of the embryo is 
now so great, that the body almost describes a com- 
plete semi-circle. The appendages pertaining to the 
head have considerably increased in size, but are 
otherwise only little changed. Still there may be 
noted on the foremost pair (a') a little sub-branch that 
indicates the lamelliform appendage. The branchial 
feet (brp) are present in their full number (8 pairs) 
and show themselves to be all deeply fissured 
and directed straight downwards. On the other 
hand, there are as yet only found 3 pairs of swim- 
ming feet (pl) in a rudimentary state, as the 4th 
pair only much later becomes developed. Neither 
is there any trace of caudal feet observed. The 
urosome itself has now, however, its full number 
of segments, and the caudal rami are distinctly 
projected and each furnished with a short bristle at 
the tip. The frontal plate (R) is now distinctly 
projectant, and the ocular stems have now assumed 
a somewhat conical form and in their external part 
exihibit the first faint indication of the formation 
of visual elements. In the mesosome, on each side 
of the intestine, there is noticed a pretty stout 
and short cylindrical sac, which evidently represents 
one of the liver sacs. The dorsal part of the an- 
terior body is still greatly blown out and filled with 
red-yellow yolk substance. Immediately below that 
part the free edges of the carapace are now dis- 
tinctly seen. The changes that the embryon has 
yet to undergo are quite successive. The remains 
of the yolk substance are little by little used 
up, and the dorsal swelling of the head becomes 
at same time reduced in size, while the valves 
of the carapace grow more and more out over the 
sides of the mesosome. The various appendages 
of the body become fully formed and occupy the 
characterstic position in relation to the body pe- 
culiar to them, causing thus the Nebalia habitus 
very soon to become prominent. Fig. 12 represents 
the young one when it is ready to abandon the 
hatching cavity. We have no difficulty whatever, 
in recognizing in it a young Nebalia. The only 
material divergence is, that there are still only 
3 pairs of swimming feet present. Of the 4th pair 
there is only seen a faint rudiment behind the 
others, in the shape of a pair of small nodular 
prominences (p'). The young one can now move 
itself freely in the water, and nourish itself; but 
some time still passes, before the various appendages 
attain their full development and acquire their nor- 
mal, abundant bristle-covering. Of all the append- 
ages, the 4th pair of swimming feet are those which 
develope themselves latest. 
