ed Bearbeidelsen af det sserdeles vidtloftige Materiale I 
af Crustaceer, indsamlede og iagttagne under Expedi- j 
tionen, har jeg fundet det praktisk rigtigt at dele min Ai- 
handling i tre Afsnit. I 2det Afsnit gives en fuldstaendig 
systematisk Fortegnelse over samtlige under Expeditionen 
iagttagne Arter med Angivelse af Eindested samt korte 
Bemaerkninger om Forekomst og Udbredning. I sidste Af- 
snit meddeles de mere almindelige Slntninger, hvortil Studiet 
af Nordhavsexpeditionens Crustaceer har ledet, dels i Hen- 
seende til Faunaens almindelige Character, dels til dens 
supponerede Bevsegelse (Ind- og Udvandring af Dyreformer) 
samt de physiske og meteorologiske Forhold, som herved 
synes at vaere bestemmende. Forste Afsnit er derimod kun 
fovbeholdt udfprlige Beskrivelser af nogle enkelte Former, 
der enten er nye for Videnskaben eller hidtil miudre luld- 
stfendigt beskrevne og afbildede. Herved er dog at marrke, 
at jeg ialmindelighed ikke har indbefattet herunder de 
Former, som tidligere er constaterede som tilbprendc Norges 
Kystfauna. Disse sidste vil paa et andet Sted blive ud- 
farligt omlmndlede, nemlig i et storre faunistisk Arbeide 
over Norges Crustaceer, som jeg med det allerforste agter 
at paabegynde. 
Til de medfplgende Plancher har jeg selv udfprt alle 
Figurer og overalt herved anvendt Camera lucida, hvorved 
deres Nojagtighed er garanteret. Til Gfrund for de fleste 
Habit usfigurer ligger color erede Tegninger udfprte af mig 
under selve Expeditionen efter friskt indfangede og endnu 
levende Exemplarer. 
De her beskrevne nye Former er tidligere kortelig 
blevne characteriserede i fplgende to paa Latin affattede 
forelpbige Afhandlinger, begge ind forte i “Arcliiv for Mathe- 
matik og Naturvidenskab”: 
1. Prodromus descriptionis Crustaceorum et Pycnogo- 
nidarwm, qvce in Expeditione Norvegica anno 1876 observavit 
G. 0. Sars. 
2. Crustacea et Pycnogonida nova in itinere 2do et 
3tio Expeditionis Norvegicce anno 1877 & 1878 colleda. 
( Prodromus descriptionis ). 
For at undgaa Gjentagelser ved Opgivelsen af Finde- 
stederne, meddeles nedenfor en Tabel over alle de Stationer, 
paa livilke Bundskrabe eller Trawl har vseret anvendt, med 
Den norske Nordhavsexpetlition. G. 0. Sars: Crustacea. 
I n working up the very extensive material embracing the 
Crustaceans collected and observed on the Norwegian 
North- Atlantic Expedition, practical reasons have induced 
me to divide my Memoir into three sections. The second 
section gives a complete systematic enumeration of the species 
observed on the Expedition, as also a statement of the localities 
where found, together with brief remarks on occurrence and 
distribution. In the third section are set forth the chief 
conclusions to which a study of the Crustacea from the 
North-Atlantic Expedition has led, partly in regard to the 
general character of the Fauna, and partly with reference 
to its supposed movements (migration of animal forms), as 
also to the physical and meteorological conditions which 
appear to detenaine the occurrence of species. The first 
section has been devoted exclusively to detailed descriptions 
of certain forms either new to science or which, up to the 
present time, have been incompletely diagnosticated and 
figured. Meanwhile, I must not fail to observe, that as a 
rule I have not included forms previously established as 
belonging to the Norwegian littoral fauna. Such forms will 
be fully treated of elsewhere, viz. in a work on the Cru- 
stacea of Norway, which I purpose beginning at an early 
date. 
For the Plates accompanying this Memoir, all of the 
figures were furnished by myself; and the use, without ex- 
ception, of the Camera Lucida affords a sufficient guarantee 
for their accuracy. Most of the habitus-representations 
are facsimiles of coloured drawings, executed by myself on 
the several cruises of the Expedition, from fresh and living 
specimens. 
The new forms described in the first section of this 
Memoir are briefly characterized in the two following preli- 
minary papers, both published in “Archiv for Mathematik 
og Naturvidenskab”: — 
1. — Prodromus descriptionis Crustaceorum et Pycno- 
gonidarum, qvas in Expeditione Norvegica anno 1876 obser- 
vavit G. 0. Sars. 
2. — Crustacea et Pycnogonida nova in itinere 2do 
et 3tio Expeditionis Norvegicce anno 1877 & 1878 colleda 
(Prodromus descriptionis). 
To avoid repetition in stating the localities, I have 
given beloAv a List of all the Stations at which the dredge 
or the trawl was used, along with the date, position of the 
1 
