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Descriptions of the Norwegian species
at present known belonging to the ...



Georg Ossian Sars




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^T^^Rnrfl^jcfiK.



HARVARD UNIVERSITY.



LIB RAR Y



MUSEUM OF OOMPABATITE ZOOLOGY.

GIFT OF

ALEX. AGASSIZ.



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FA NOR G



Vol. I.



DESCRIPTIONS OF THE NORWEGIAN SPECIES AT PRESENT KNOWN
BELONGING TO THE SUB-ORDERS



PHYLLOCARIDA and PHYLLOPODA



BY



G. O. SARS



WITH 20 PLATES, COLOURED AND UNCOLOURED



CHRISTIANIA

PRINTED BY THE JOINT-STOCK PRINTING COMPANY
(Formerly: Det Mallingske Bogtrykkeri.)

1896



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FORTALE



PREFACE.



Neervaerende Vserk, til hvis Udgivelse Staten
liar bevilget de fomodne Midler, blev paabegyndt
for mere end et Deeennium siden; men forskjellige
uforudseede Omsteendigheder bar bevirket, at Ud-
arbeidelsen af samme i Isengere Tid bar maattet
standses, saa at ferst nu Vserket kan udkorame i
sin Helhed. Oprindelig var Bevillingen givet til
den fortsatte Udgivelse af Fauna Uttoralis Norvegice,
bvoraf tidligere er udkommet 3 Bind, forfattede
dels af min Fader alene, dels af bam i Forening
med nu afdede Overlaege Danielssen og Konservator
Koren. Da det forekom mig, at denne Titel paa en
mindre beldig Maade vilde komme til at begrsendse
StofFet, tilled jeg mig at foreslaa, at Benaevnelsen
Uttoralis udgik og at Vserket berefter skulde ud-
komme under den ber anvendte Titel. Det af mig
til nservserende Bind valgte Stof er ogsaa af den
Art, at det vanskeligt vilde passe indenforRammen
af den tidligere Titel, da jo ber ikke blot Sedyr,
men ogsaa en Del aegte Ferskvandsdyr er omband-
lede. Idetbele syntes mig, at den mere omfattende
Titel, Fauna Norvegim, bedre maatte kunne svare
til sin Hensigt, da der berunder vil kunne leveres
Bidrag til Belysning af bvilkensombelst Branebe af
vor Fauna, der maatte frembyde en saerlig Inter esse.
I Overensstemmelse med de 3 udkomne Bind af
Fauna Uttoralis, tror jeg at nserveerende Vserk bor
indebolde Afbandlinger af en mere udforlig ana-
tomisk-biologisk Cbaracter, bebandlende visse ud-
valgte Dele af vor Fauna og udstyrede paa en saa-
vidt muligt tidsmsessig Maade, saavel bvad Text
som Plancber angaar. I et andet, paa engelsk skre-
vet Vserk bar jeg paabegyndt en Bearbeidelse af
vor Fauna efter et berfra temmelig forskjelligtPrin-
cip, idet dette Vserk er nsermest beregnet paa at



Tbe present work, for tbe publication of wbicb
tbe Government bas granted tbe necessary funds,
was begun more tban ten years ago; but various
unforeseen circumstances baving combined to put a
stop to tbe preparation of tbe work for a considerable
time, it is only now tbat it can be publisbed in its
entirety. Tbe grant was originally given for tbe
continued publication of Fauna Uttoralis Norvegice,
of wbicb tbree volumes bad already been publisbed,
written partly by my fatber alone, partly by
bim in conjunction witb tbe late Dr. Danielssen,
and Curator Koren. As it seemed to me tbat tbis
title would limit tbe subject-matter somewbat
infelicitously, I ventured to suggest tbat tbe desig-
nation Uttoralis sbould be struck out, and tbat tbe
work sbould bereafter appear under tbe title bere
employed. Tbe matter cbosen by me for tbe pre-
sent volume, is also of sucb a kind, tbat it could
bardly be included under tbe former title, as not
only marine animals, but also some true fresb-water
animals are bere treated of. Upon tbe wbole, it
seemed to me tbat tbe more comprebensive title.
Fauna NorvegicB, would better answer its purpose, as
under it, contributions migbt be made to tbe infor-
mation concerning any brancb of our fauna tbat
migbt offer special interest. In accordance witb tbe
3 publisbed volumes of Fauna Uttoralis, I tbink tbat
tbe present work sbould contain treatises of a more
exbaustive anatomical-biological cbaracter, dealing
witb certain parts of our fauna, and got up as
far as possible in a manner suitable to tbe times,
as regards text and plates. In anotber work,
written in Englisb, I bave begun an account of our
fauna on a very different principle to tbis, as it is
ratber calculated to give, as far as possible, a brief,



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VI



give en saavidt muligt kortfattet systematisk Over-
sigt af samtlige hidtil kjendte norske Arter, hvor-
ved der er lagt hovedsagelig Veegt paa dets prak-
tiske Anvendelighed ved Artsbestemmelsen, mindre
paa det ydre Udstyr eller paa en mere indgaaende
anatomisk Behandling af de enkelte Former. Jeg
tror, at zoologiske Arbeider udarbeidede efter ethvert
af disae Prineiper bar sin fulde Berettigelse og Nytte
Side om Side, og skulde ogsaa af denne Grund 0nske,
at Fauna Norvegioe blev forbeholdt mere udforlige
Monographier af enkelte mindre kjendte Dyreformer
eller af begrsendsede Grupper, der maatte frem-
byde en sserlig Interesse i anatomisk-biologisk Hen-
seende.

Plancheme til nservserende Bind er i sin Tid
udforte paa nu afdede Lithograf Lynghs Officin, og
ved deres Udferelse er anvendt al den Omhyggelig-
hed og Kunst, som da kunde prsesteres, saavel hvad
Lithographering som Farvetrykning angaar. Texten
er i Lighed med de 2 sidsteBind Q,i Fauna littoralis
og med Nordhavs-Expeditionens Generalberetning,
dobbeltspaltet, den ene Spalte norsk, den anden en-
gelsk. Oversaettelsen af de 6 ferste Ark er besorget
af nu afdede Translateur Wilson, Resten af Miss
Jessie Muir.

Idet jeg herved fremlsBgger for Offentligheden
Iste Bind af Fauna I^orvegice, sker det med det
Haab, at der maa gives vore fremtidige Zoologer
Anledning til at fortsaette dette Vserk med flere
paafolgende Bind udstyrede paa en for vort Land
vaerdig Maade.

Forf atteren.



systematic survey of all the hitherto known Nor-
wegian species, whereby special importance is laid
on its practical applicability in the determination
of species, and less on its external get-up, or on a
more detailed anatomical treatment of the various
forms. I think that zoological works written on
these two principles are perfectly legitimate and
useful side by side ; and I therefore wish that Fauna
Norvegits could be kept for more detailed mono-
graphs on certain less familiar animal forms, or of
limited groups that offered special interest in an
anatomical-biological direction.



The plates to the present volume were executed,
in their time, in the late lithographer Lyngh's
printing-office, and all the care and art of which
that time was capable, both as regards lithography
and colour-printing, were employed in their execu-
tion. The letter-press is similar to that of the last
2 volumes of Fauna littoralis^ and to the General
Report of the North Atlantic Expedition, being in two
columns, the one column Norwegian, the other Eng-
lish. The translation of the first 6 sheets was made
by the late Mr. Wilson, translator, the remainder
by Miss Jessie Muir.

In now presenting the first volume of Fauna
NorvegitB to the public, I do so in the hope that
opportunity may be given to our future zoologists
to continue this work with successive volumes, got
up in a manner worthy of our country.

The Author.



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INDHOLD.



Pag.

Indledning 1-

Phyllocarida 4.

Fam. Nehaliidce 6.

Gen. Nehalia, I^ach 7.

1. Nebalia bipes (Fabr.; 9.

2. Nebalia typhlops, G. O. Sars 31.

Phyllopoda 36.

Seciio I. Anostraca 39.

Fam, 1. Branchipodidcs 40.

Gen. Branchinecta, Verrill 40.

Branchineeta paludosa (MttUer; 41.

Fam. 2. Polyartemiidas 68.

Gen. Polyariemia, Fischer 58.

Polyartemia forcipata, Fischer 69.

Sectio 11. Notostraca 66.

Fam, Apodidce 67.

Gen. LepiduruSy Leach 67.

Lepidurus glacialis (Kroyer) 68.

Sectio III. Conchostraca 83.

Fam. 1. Limnadiidce 84*

Gen. Limnadia, Brogniart 86

Limnadia lenticularis (Lin.) 86]

Fam. 2. Limnetidce 116

Gen. LimnetiSy Lov^n 116

Limnetis brachyurus (Mttll.) 117.



CONTENTS.



Pag.

Introduction 1.

Phyllocarida 4.

Fam. NebaliidcB 6.

Gen. Nehalitty Leach 7.

1. Nebalia bipes (Fabr.) 9.

2. Nebalia t>T)hlop8, G. O. Sars 81.

Phyllopoda 35.

Section I. Anostraca 39.

Fam. 1. Branchipodidce 40.

Gen. Branchineeta, Verrill 40.

Branchineeta paludosa (Mttller) 41.

Fam, 2. PolyartemiidcB 68.

Gen. Polyartemia^ Fischer . 68.

Polyartemia forcipata, Fischer 69.

Section II. Notostraca 66.

Fam. Apodidce 67.

Gen. Lepidurus, Leach 67.

Lepidurus glacialis (Kroyer) 68.

Section III Conchostraca 83.

Fam. 1. Limnadiidce 84.

Gen. Limnadia, Brogniart 86.

Limnadia lenticularis (Lin.) 86.

Fam. 2. Limnetidce 116.

Gen. Limnetis, Lov^n 116.

Limnetis brachyurus (Mflll.) 117.



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INDLEDNING.



Crustaceernes vidtloftige Classe inddeles, som
bekjendt, lalmindelighed i to store Afdelinger, Mala-
costraca, eller de heiere Krebsdyr, og Entoinostraca,
eller de saakaldte Smaakrebse. Enhver af disse
Afdelinger lader sig igjen dele i 4 Grupper eller
Orde»er. Til den ferste barer 1) Podophthalmata,
eller de stilkoiedeKrebse (Decapoda, Schizopoda og
Stomatopoda), 2) Cumacea, 3) Isopoda og 4) Amphi-
poda\ til den sidste: 1) Branchiopoda, 2) Ostracoda^
3) Cirripedia, og 4) Copepoda. Hertil kommer endnu
den i mange Henseender meget anomale, og i visse
Punkter med Arachniderne beslsegtede Gruppe, Xipho-
surce, eller Dolkhalerne, som dog af flere Natur-
forskere ikke benregnes til Crustaeeerne, men be-
tragtes som Typen for en egen Arthropodeclasse.
Naar undtages denne sidste Gruppe, er alle de
evrige ovenanforte Ordener vel reprsesenterede i vor
Fauna. For det ferste vil vi alene komme til at
beskjsBftige os med den ferste af de til Entomostra-
ceeme horende Ordener, Branchiopoda. Denne Orden
bar faaet sit Navn deraf, at et storre eller mindre
Antal af de bag Munddelene falgende Lemmer an-
tager en eiendommelig bladdannet Struetur, der gjer
dem fortrinlig skikkede til at fungere som Respira-
tionsorganer, om de end i enkelte Tilfselde paa
samme Tid kan fungere som Svemmeapparater.
Undertiden, saaledes bos visse Cladocerer, kan disse
Lemmers saavel respiratoriske som motoriske Func-
tion vsere meget redueeret, bvorimod de faar sin
vaesentligste Betydning som Griberedskaber, der
understotter Munddelene ved at fastbolde og bringe
til Munden de Fodemidler, hvoraf disse Dyr lever,
en Function, som imidlertid ogsaa for en Del kan
paavises bos Former med forevrigt normalt udvik-
lecle Branchialfodder, f. Ex. Apus, Ogsaa bos fuld-

1 — G. 0. Sars: Fauna Norvegiie.



INTRODUCTION.



As is known, tbe extensive class Crustacea is,
in general, classified into two great divisions viz.,
Malacostraca, or tbe bigber Crustaceans, and En-
tomostraca^ or tbe so-called lower Crustaceans.
Eacb of tbose divisions may be subdivided, again,
into 4 groups or orders. To the first division per-
tain: — 1) Podophthalmata or tbe stalk-eyed Crusta-
ceans (Decapods, Scbizopods and Stomapods), —
2) Cumacea, — 3) Isopoda, and — 4) Amphipoda. To
the second division pertain: — 1) Branchiopoda, —
2) Ostracoda, — Cirripedia, and — 4) Copepoda. To
them is added the Xiphosuree, or sword-tails — in
many respects very anomolous, and in certain cha-
racters related to the group Arachnida — which
are by several naturalists, however, not assigned to
the Crustaceans, but is considered to be tbe type
of a special class af Arthropods. With the excep-
tion of that last-named group all the other above-
mentioned orders are well represented in the Nor-
wegian Fauna. At present we shall only occupy
ourselves with tbe first of tbe orders pertaining to
the Entomostracans viz: Branchiopoda. This order
has obtained its appellation from the circumstance,
that a larger or smaller number of the appendages
behind tbe oral parts assume a peculiar foliaceous
structure, which causes them to be admirably
adapted to serve as respiratory organs, even although
they, in a few cases, may at same time serve as
swimming apparatuses. Occasionally, as in certain
Cladocerans, both tbe respiratory and motoric func-
tions of these appendages may be greatly diminished;
and their essential importance becomes that of a
prehensile-apparatus which aids the oral parts in
securing and carrying to the mouth tbe nutriment
upon which these animals feed; a function which



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kommen typiske Branchiopoder vil vi finde, at Lem-
merne, ved Siden af sin Function som Respirations-
organer, altid er af vsesentlig Betydning for Til-
• veiebringelsen af Feden, idet de ved sine rythmiske
Bevsegelser frembringer en oontinuerlig Stremning
af Vandet ind mod Munden, hvorved de Smaa-
partikler, hvoraf Dyret lever, bringes indenfor Mund-
delenes Omraade. I ethvert Fald maa den oven-
omtalte eiendommelige Modification af Lemmeme,
hvortil vi egentlig ikke bar noget tilsvarende hos
andre Crustaceer, betragtes som den for de her om-
handlede Dyr vigtigste og mest udprsegede Cha-
racter.



Branchiopodeme indtager i flere Henseender en
central Stilling inden Crustaceernes Classe, og Prof.
Claus bar endog fremsat den Hypothese, at alle
nulevende Crustaceer i sidste Instans nedstammer
fra en phyllopodeagtig Dyreform (Protophyllopod).
Skjondt denne Hypothese af andre Zoologer (Packard)
bar vseret bestridt, er der dog al Grund til at an-
tage, at disse Dyr bar conserveret adskillige Cha-
racterer, der efter al Sandsynlighed er i hoi Grad
primitive og maaske endog skriver sig fra de seldste
paa vor Klode optrsedende Artbropoder. Allerede
det i hoi Grad varierende og ofte excessivt foregede
Antal Kropssegmenter, samt disses ialmindeligbed
mindre skarpt udprsegede Gruppering til distincte
Kropsafsnit, synes at vise, at vi her bar at gjore
med Former af en kun lidet udarbeidet Character,
bos bvem endnu ikke det for Nutidens Crustaceer
typiske Forbold rigtigt bar fsestnet sig; og bvad
Lemmernes Bygning angaar, saa er vel alle enige i
at de, ialfald bos de typiske Branchiopoder, reprse-
senterer et mere primitivt Standpunkt end hos nogen
af de ovrige Crustacegrupper. Ogsaa bvad den indre
Organisation angaar, findes bos de berben borende
Former kun lidet fixerede Forbold, men derimod en
Mangfoldigbed af Modification er i Bygningen af snart
sagt alle Organer, bvad der ligeledes giver denne
Crustacegruppe et ganske eiendommeligt Praeg lige-
overfor de ovrige Ordener. Endelig vil vi i disse
Dyrs Levevis, Forplantning og Udvikling stode paa
baade cbaracteriske Forskjelligbeder mellem de for-
skjellige Former og tildels ogsaa hoist eiendomme-
lige, fra samme bos andre Crustaceer afvigende For-
bold. Et noiere Studium af denne Crustacegruppe
vil derfor ogsaa vsere af sserlig Interesse, saavel i
pbylogenetisk som biologisk Henseende og vil pas- i
sende kunne tjene som Udgangspunkt ved Bearbei-
delsen af den her ombandlede Dyrclasse.



may also, to some extent, be demonstrated in forms
with otherwise normally developed branchial-legs
e. g. Apus. Also in perfectly typical Branchiopods
we may observe that the appendages, besides their
function as respiratory organs, are always of mate-
rial importance in the procuring of the nutriment,
as they by their rhythmical movement produce a
continuous current of the water in towards the
mouth, by which the minute particles upon which
the animal exists are brought within the range of
the oral parts. At any rate, the above mentioned
peculiar modification of the appendages, to which
we meet with nothing really correspondent in other
Crustaceans, must be considered to be the most
important and prominent characteristic of the ani-
mals here spoken of.

The Branchiopods occupy, in several respects, a
central position in the class of the Crustaceans, and
Prof. Claus has even proposed the hypothesis, that
all the now-existent Crustaceans may descend, in
the final instance, from a phyllopodous animal-form
(Protophyllopod). Although that hypothesis has been
rejected by other zoologists (Packard), there is still
every reason to assume that those animals have
retained several characteristics which are, in all
probability in a high degree primitive, and perhaps
even emanate from the oldest Arthropods that
have appeared on our Earth. The extremely^ vari-
able and frequently excessively increased number
of body-segments, as well as in general their
less distinctly prominent grouping into distinct
sections, at once appears to point to the circum-
stance that we have here to do with forms of only
vaguely developed character, in which the typical fea-
tures characteristic of the modernly existent Crusta-
ceans, have not yet become permanently established :
and as regards the structure of the appendages all
unite, we believe, in the opinion that it, at any rate
in the typical Branchiopods, represents a more pri-
mitive condition than in any of the other groups
of Crustaceans. Also in regard to the internal or-
ganization there is found, in the forms belonging
to this order, only little of permanent features but,
on the other hand, a multitude of modifications in
the structure of, it may be said, all the organs,
a circumstance that also imparts to this group of
Crustaceans a quite peculiar imprint compared with
the other orders. Finally we meet in these ani-
mals' mode of life, propagation and development,
both characteristic differences between the various
forms and partly, also, highly peculiar features
differing from those in other Crustaceans. A closer
study of this group of Crustaceans will, therefore,
prove of special interest, both in pbylogenetic
and biological respects, and will serve as a suitable
point of departure in the treatment of the animal-
class here spoken of.



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Branchiopodernes Orden lader sig naturligt ind-
dele i 4 imderordnede Grupper, eller Underordener,
der saavel hvad den ydre Habitus som den anato-
miske Bygning angaar, skiller sig temmelig skarpt fra
hinanden. Disse Underordener er folgende: VjPhyllo-
carida, 2) Phyllopoda, 3) Cladocera og 4) Branchiura.
De 2 ferste af disse Underoi'dener vil blive gjorte
til Gjenstand for en neiere Behandling i nservserende
Bind af Fauna Norvegice.



The order of Branchiopods may be naturally
divided into 4 subordinate groups or sub-orders,
which, both in regard to external habitus and ana-
tomical structure, distinguish themselves pretty
sharply from each other. These sub-orders are, as
follows viz: 1) Phyllocarida^ — 2) Phyllopoda^ —
3) Cladocera^ and — 4) Branchiura. The two first-
named sub-orders will be made the subject of a
closer treatment in the present volume of Fauna
Norvegice,



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Subordo I.

PHYLLOCARIDA

(Leptostracaj Claus).



Character. — Branchiopoder med den forreste
Del af Legemet dsekket af et stort, mere eller min-
dre udpraeget tveklappet Rygskjold, forsynet fortil
med en bevsegelig Pandeplade. Den bagre Del af
Kroppen cylindrisk, afsmalnende bagtil og endende
med 2 bevaegelige Grenfe (Furca), mellem hvilke der
undertiden er en dolkformig Haleplade. 0inene stil-
kede og bevsegelige. BeggePar Folere yel udviklede,
mangeleddede, 2det Par enkle, hverken locomotoriske
eller prehensile. AUe Forkropslemmer bag Mund-
delene udelukkende respiratoriske ; Bagkropslem-
merne meget ulig disse og fordetmeste locomotoriske,
manglende paa de bagerste Segmenter. Havdyr.



Aim. Bemserkninger. — Typen for denne Under-
orden er den i mange Henseender hoist maerkveer-
dige og anomale Slaegt Nebalia, om hvis systematiske
Stilling der har hersket den storste Uenighed blandt
Zoologerne. Medens man for ialmindelighed med
Milne-Edwards henregnede denne Form til Phyllo-
poderne, har i den nyere Tid, navnlig efter de af
Prof. Claus anstillede Undersogelser, en ganske anden,
allerede meget tidligt af enkelte Naturforskere ytret
Opfatning vundet Overhaand, nemlig at denne Form
slutter sig nsermest til de stilkoiede Krebsdyr, navn-
lig til visse Schizopoder (Euphausiidse), og at den
saaledes snarere tilhorer Malacostraceernes Afdeling
end Entomostaceerne. . Jeg har paa et andetSted^)
nsermere udviklet mine Grunde til fremdeles at bi-
beholde denne Slaegt under Entomostraceerne, og
blandt disse er Branchiopoderne de, hvormed nser-



*) Report on the Phyllocarida, collected during the Expedition
of H. M. S. «Challenger>.



Sub-Order I.



PHYLLOCARIDA

(Leptostraca, Claus).



Characters. — Branchiopods, with the foremost
portion of the body covered by a large, more or
less distinctly bi-lobate carapace, furnished anteri-
orly with a mobile frontal plate. The posterior por-
tion of the body cylindrical tapering backwards, and
terminating in 2 mobile rami (furca), between which
there is occasionally a mucroniform caudal plate.
Eyes pedunculated and mobile. Both pairs of antennse
well developed, multiarticulate; 2nd pair simple,
neither locomotory nor prehensile. All the appen-
dages of the anterior division of the body behind
the oral parts, exclusively respiratory. The appen-
dages of the posterior division of the body very
unlike the former and chiefly locomotory; absent
on the posterior segments. Marine animals.

Oeneral remarks. The type of this sub-order
is — the in many respects highly remarkable and
anomalous genus — Nebalia, regarding whose sys-
tematic position the greatest difference of opinion
has prevailed among zoologists. Whilst, previously,
zoologists in general agreed with Miln€-Edwards
in assigning this form to the Phijllopods, there has
prevailed in later times, especially since the result
of the investigations made by Prof. Claus, a
quite different opinion, which already much earlier



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