ved Spidsen og i Inderkanten. Ingen median Hale- 

 plade tilstede. Den indre Organisation nærmest lig 

 samme hos Ampliipoderne. Æggene gjennemgaar 

 sin Udvikling indenfor Rvgskjoldets Valvler, mel- 

 lem Forkroppens Brancliialfodder. Ungens Udvikling 

 directe, uden Metamorpliose. 



Bemærkninger. — Indtil for ganske nylig kjeudte 

 man af nærværende Familie kun en eneste Slægt 

 nemlig Slægten NehaJia. Under Cliallenger-Expedi- 

 tionen blev imidlertid opdaget "2 lierlien hørende 

 Former, der begge danner Typer for særskilte Slæg- 

 ter og nærmere er omtalte i min Bearbeidelse af de 

 under denne Expedition indsamlede Phyllocarider. 

 Begge disse Slægter udmærker sig ved den eien- 

 dommelige Udvikling af Branchialfodderne. Medens 

 disse hos den ene Slægt, Faranehalin Claus, er, 

 navnlig hos Hunnen, ualmindelig stærkt forlængede, 

 saa at de i visse Henseender selv minder om For- 

 kropslemmerne hos visse Sehizopoder (Euphausiidæ), 

 er de hos den anden Slægt, Xehaliopsis Gr. O. Sårs, 

 reducerede til meget smaa, utydeligt lappede, mem- 

 branøse Plader, der viser endnu mindre Lighed med 

 sædvanlige Fodder end hos de mest tj-piske Branchio- 

 poder. Den 3die Slægtr Nebalia, staar i Henseende 

 til Brancliialfoddernes Udvikling paa en Maade midt 

 imellem hine 2 Slægter og repræsenterer saaledes 

 det for Familien typiske Forhold. I Henseende til 

 den ovrige Organisation sj'nes der ikke at være 

 synderlig stor Forskjel mellem de 3 Slægter, oraend 

 man ogsaa her forefinder Characterer af ixtvivlsom 

 generisk Betydning. Alene den typiske Slægt. Xe- 

 balia, er representeret i vor Fauna. 



Gen. Nebalia. Leach. 



powerful bifurcate swimming legs: the 2 succeeding 

 pairs rudimentary. The 2 last segments without 

 anj- 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 Am])hipods. The ova undergo their develop- 

 ment inside the valves of the carapace, between the 

 branchial legs of the anterior division of the Ijod}'. 

 The development of the young direct, without an}' 

 nietamorpho.<is. 



Remarks. — Until quite latelv we knew only 

 a single genus of this family viz., the genus yehalia. 

 There were collected on the Ciiallenger 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 Ph\'llo- 

 carida collected by that Expedition. Both of those 

 genera distinguish themselves by the peciiliar devel- 

 opment of the branchial legs. AVhilst these in the 

 one genus, I'aratiebalia, Claus. are. especially in the 

 female, unusually greatly prolonged, so that in 

 certain respects they even remind one of the ajjpen- 

 dages of the anterior division of the bodj- in certain 

 Schizopods (Euphausiidæ , they are in the other 

 genus, Nebaliopsis, G. 0. Sars, reduced to very small, 

 indistinctly lobate membranoi^s plate.< that show 

 still less resemblance to ordinary legs than in the 

 most tj'pical Branchiopods. The 3rd genus, Xelalia. 

 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 (if the family. In regard to the rest of the 

 organization there does not appear to be any mate- 

 rial ditterence between the 3 genera, although we, 

 here, also tind characteristics of indubitable genei'ic 

 importance. Onlj* the typical genus, Xebalia, is 

 represented in the Norwegian Fauna. 



Gen. Nebalia, Leach. 



Slægtscharacter. — R^-gskjoldet stærkt sanimen- 

 trykt, bagtil i Midten dybt indbugtet. Sidelappene 

 af betydelig Storrelse. bredt afrundede og dækkende 

 næsten hele det forreste Afsnit af Bagkroppen. 

 Pandepladen smalt tungeformig, med eller uden ter- 

 minal Spina. Truncus forholdsvis kort. Bagkroppen 

 betydelig længere end Forkroppen, jevnt afsmalnende 

 bagtil, uden skarp Begrændsning mellem det forreste 

 og bagerste Afsnit. Oinene mere eller mindre ud- 

 viklede, hvert ved Basis dækket af en tilspidset, 

 skjælformig Plade De ovre Følere kortere end de 

 nedre. Skaftet 4-leddet, med en stærk knæforniig 

 Boining mellem 2det og 3die Led; sidste Led noget 

 udvidet mod Enden og lobende fortil ud i et kort. 



Generic characters. — Carapace greatlj' com- 

 pressed, deeph- insinuated in the middle jiosteri- 

 orly, the lateral lobes of considerable size, broadly 

 rounded and covering nearly the entire fi"ont section 

 of the posterior division of the l)ody. Frontal plate 

 narrow linguiform, with or without terminal spina. 

 Truncus relatively short. The posterior division of 

 the body considerabh' longer than the anterior 

 division, tapeiing evenly l)ackwards, without sharji 

 demarcation between the foremost and hindmost 

 sections. Eyes more or less developed, each covered 

 at the base by an acumiimte sijuamiform plate. 

 Superior antennæ shorter than the inferior ones; 

 peduncle 4-jointeil with a strong geniculate bend 



