ved Spidsen og i Inderkanten. Ingen median Hale- 
plade tilstede. Den indre Organisation nermest lig 
samme hos Amphipoderne. Mggene gjennemgaar 
sin Udvikling indenfor Rygskjoldets Valvler, mel- 
lem Forkroppens Branchialfodder. Ungens Udvikling 
directe, uden Metamorphose. 
r 
Bemerkninger.— Indtil for ganske nylig kjendte 
man af nerveerende Familie kun en eneste Slegt 
nemlig Slegten Nebalia. Under Challenger-Expedi- 
tionen blev imidlertid opdaget 2 herhen horende 
Former, der begge danner Typer for serskilte Sleg- 
ter og narmere er omtalte i min Bearbeidelse af de 
under denne Expedition indsamlede Phyllocarider. 
Begge disse Slegter udmerker sig ved den eien- 
dommelige Udvikling af Branchialfodderne. Medens 
disse hos den ene Slegt, Paranebalia Claus, er, 
navnlig hos Hunnen, ualmindelig sterkt forlengede, 
saa at de i visse Henseender selv minder om For-. 
kropslemmerne hos visse Schizopoder (Euphausiide), 
er de hos den anden Slegt, Nebaliopsis G. O. Sars, 
reducerede til méget smaa, utydeligt lappede, mem- 
brangse Plader, der viser endnu mindre Lighed med 
seedvanlige Fedder end hos de mest typiske Branchio- 
poder. Den.3die Slegt, Nebalia, staar i Henseende 
til Branchialfoddernes Udvikling paa en Maade midt 
imellem hine 2 Slegter og representerer saaledes 
det for Familien typiske Forhold. I Henseende til 
den ovrige Organisation synes der ikke at vere 
synderlig stor Forskjel mellem de 3 Slegter, omend 
man ogsaa her forefinder Characterer af utvivlsom 
generisk Betydning. Alene den typiske Slegt, Ne- 
balia, er representeret i vor Fauna. 
Gen. Nebalia, Leach. 
Slegtscharacter. — Rygskjoldet sterkt sammen- 
trykt, bagtil i Midten dybt indbugtet, Sidelappene 
af betydelig Storrelse, bredt afrundede og dekkende 
nesten hele det forreste Afsnit af Bagkroppen. 
Pandepladen smalt tungeformig, med eller_nden ter- 
minal Spina. Truncus forholdsvis kort. Bagkroppen 
betydelig lengere end Forkroppen, jevnt afsmalnende 
bagtil, uden skarp Begreendsning mellem det forreste 
og bagerste Afsnit. @inene mere eller mindre ud- 
viklede, hvert ved Basis dekket af en tilspidset, 
skjelformig Plade. De ovre Folere kortere end de 
nedre, Skaftet 4leddet, med en sterk kneformig 
Boining mellem 2det og 3die Led; sidste Led noget 
udvidet mod Enden og lobende fortil ud i et kort, 
powerful bifurcate swimming legs; the 2 succeeding 
pairs rudimentary. The 2 last segments without 
any ventral appendages. Caudal rami simple, linear 
or lamellar, closely beset with bristles at the tip 
and on the inner edge. No medial caudal plate. 
Internal organization approximating closest to that 
of the Amphipods. The ova undergo their develop- 
ment inside the valves of the carapace, between the 
branchial legs of the anterior division of the body. 
The development of the young direct, without any 
metamorphosis. 
Remarks. — Until quite lately we knew only 
a single genus of this family viz., the genus Nebalia. 
There were collected on the Challenger Expedition, 
however, 2 forms pertaining to the family, which 
both form types of special genera, and are more 
particularly described in my Report of the Phyllo- 
carida collected by, that Expedition. Both of those 
genera distinguish themselves by the peculiar devel- 
opment of the branchial legs. Whilst these in the 
one genus, Paranebalia, Claus, are, especially in the 
female, unusually greatly prolonged, so that in 
certain respects they even remind one of the appen- 
dages of the anterior division of the body in certain 
Schizopods (Euphausiide), they are in the other 
genus, Nebaliopsis, G.O. Sars, reduced to very small, 
indistinctly lobate membranous plates that -show 
still less resemblance to ordinary legs than in the 
most typical Branchiopods. The 3rd genus, Nebalia, 
stands, in regard to the development of the branchial 
legs, in a manner intermediate between those two 
genera, and thus represents the relation that is 
typical of the family. In regard to the rest of the 
organization there does not appear to be any mate- 
rial difference between the 3 genera, although we, 
here, also find characteristics of indubitable generic 
importance. Only the typical genus, Nebalia, is 
represented in the Norwegian Fauna. 
Gen. Nebalia, Leach. 
Generic characters. — Carapace greatly com- 
pressed, deeply insinuated in the middle posteri- 
orly, the lateral lobes of considerable size, broadly 
rounded and covering nearly the entire front section 
of the posterior division of the body. Frontal plate 
narrow linguiform, with or without terminal spina. 
Truncus relatively short. The posterior division of 
the body considerably longer than the anterior 
division, tapering evenly backwards, without sharp 
demarcation between the foremost and hindmost 
sections. Eyes more or less developed, each covered 
at the base by an acuminate squamiform plate. 
Superior antenne shorter than the inferior ones; 
peduncle 4-jointed with a strong geniculate bend 
