Buccinmidæ. 
Af denne Familje har Expeditionen bragt tilveie et 
Materiale af en ganske betydelig Størrelse, og da det er 
samlet under en gradvis Fremtrængen fra 60de til 80de 
Breddegrad og ligeledes under en stor Vidde fra Øst til Vest 
(fra Jan Mayen til henimod Novaja Semlja), kaster det et Lys 
over Arternes Variation under de forskjellige geografiske 
Forholde, der er af stor Interesse. De talrige levende 
Exemplarer har ogsaa givet en rig Anledning at undersøge 
den saa meget paaagtede Tandstrukturs Stabilitet. I en 
lille Afhandling “Ueber die Variationen der Zahnstructur 
bei dem Genus Buccinum” (Jahb. d. Mal. Gesell. 1879) 
paaviste jeg, at der hos Buccinwm ikke tør tillægges Tand- 
formerne stor Betydning som Artskarakter. I det følgende 
vil det ogsaa vise sig, at inden Neptunea yder denne Karakter 
lidet tilfredsstillende Holdepunkter, men saa slemt som hos 
den anden Slægt er det dog ikke. 
Uagtet det saaledes temmelig negative Resultat, som 
Undersøgelserne af Tandstrukturen har bragt til Gunst for 
Arterne, saa maa jeg dog indrømme denne Karakter den 
største Betydning for Classificationen, men før man kan 
gjennemføre en frugtbringende Revision med Tandstruk- 
turen som væsentligt Grundlag, er det nødvendig at have 
fuld Oversigt over Formerne. Hos Familjen Buccinide er 
der endnu neppe nok gjort tilfredsstillende Undersøgelser 
til, at man med fuld Tryghed kan bevæge sig. Der er 
vistnok al Sandsynlighed for at flere Slægter, saasom 
_ Troschelia (Mørch) og Jumala n. gen. ikke vil beholde sin 
Plads under Buccimide, (bvad den første Slægt angaar, 
da har ogsaa Prof. G. O. Sars o. fl. udskilt den og placeret 
den under Fussiolariderne; den sidste burde da med samme 
Ret sættes under Columbella eller Buccinopsis), men for- 
uden disse to er der ogsaa Pyrolofusus, Volutopsis, Mohmia 
samt en Art af Siphonorbis, der ikke lader sig indordne 
under den Ramme, som Troschel har draget for Familjen 
Buccinina, nemlig: Centralpladen 4 til 7 og Sidepladen 4 
eller 8 Tænder (Gebiss d. Schnecken Vol. 2, Pg. 69); thi 
de har alle kun 2 Tænder paa Sidepladen og for Mohnias 
Buceinidæ. 
For the study of this family of mollusca, the Nor- — 
wegian North-Atlantic Expedition has been fortunate in 
securing a rich collection of materials, which, obtained as 
it was by the gradual exploration of a tract stretching from 
the 60th to the 80th parallel of latitude, and east and 
west from the island of Jan Mayen almost to Novaja 
Zemlja, cannot fail, by the disclosure of many interesting 
data, to throw light on the varying character of the species 
under different biological conditions. The numerous living 
specimens have also furnished ample opportunity of investi- 
gating the stability of the dentition, to which attention 
has been so largely directed. In a brief Memoir, be- 
aring title: — “Ueber die Variationen der Zahnstructur bei 
dem Genus Buccinum” (Jahrb. d. Mal. Gesell. 1879), I 
have pointed out, that but little weight, im Buccinwn, 
can be attached to the structure of the teeth as a specific 
character. In Neptunea, too, as will afterwards appear, 
diversity of dentition affords anything but a trustworthy 
guide, though certainly less deceptive than in the foregoing 
genus. 
But, negative, accordingly, upon the whole, as is the 
result of research touching the value of dentition in fur- 
nishing a distinct specific feature, I readily grant to that 
character the greatest importance in facilitating elassi- 
fication. Meanwhile, a thoroughgoing revision, specially 
founded on the structure of the teeth, implies an intimate 
knowledge of the forms. Now, the family Buccinide can 
hardly as yet have been sufficiently investigated to give a safe 
footing for systematical arrangement to clear up every doubt- 
ful pomt. Several genera, such as Troschelia (Mérch) and 
Jumala, n. g., will, most probably, in future, cease to rank 
under Buccinide; indeed, Professor G. O. Sars and other 
naturalists have already excluded the former, placing it 
under Fussiolaride, and the latter may with equal reason 
be classed under Colwmbella or Buccinopsis. Exclusive, 
however, of the two aforesaid genera, those of Pyrolofusus, 
Volutopsis, Mohnia, and a species of Siphonorbis, cannot be 
brought within the limits defined by Troschel for the family 
of Buccinina, viz: — the central plate with from 4 to 7 cusps, 
and the laterals with 4 or 3 cusps (Gebiss d. Schnecken, 
Vol. 2, p. 69); for they have all 2 cusps on the lateral 
