Naar den norske Nordhavsexpeditions ,, mollusker-' 

 forst nu kan faa sin afslutning, har dette sin grund i at 

 andre gjøremaal saa stærkt har optaget min tid og tvunget 

 mig at udsætte fra aar til andet med tilendel)ringelsen af 

 arbeidet. 



Vistnok har samlingerne ligget bestemte og ordnede, 

 men til en ny kritisk gjennemgaaelse af især de mindre 

 arter, vil ikke længer mine øine gjøre mig fuld tjeneste, 

 jeg har derfor formaaet min nevø, konservator James A. 

 Grieg, at være min medarbeider i dette afsluttende arbeide. 



Bergen i april 1901. 



Herman Friele. 



That the 'Mollusca' of the Norwegian North Atlantic 

 Expedition has only now been brought to a conclusion, is 

 accounted for by the fact that othor duties have occupied 

 me and obliged me to defer the conclusion of my work 

 from year to year. 



The collections, it is true, have long been determined 

 and arranged, but my eyes will no longer serve me com- 

 pletely for a new critical study of the species, especially 

 the smaller ones. I have therefore prevailed on my nephew, 

 Curator James A. Grieg, to be my collaborator in this 

 concluding labour. 



Bergen. Aiyril, 1901. 



Hermau Friele. 



Første bind af Nordhavsexpeditionens mollusker om- 

 handler bucrinidæ, andet bind slægten hela samt nogle dels 

 sjeldnere, dels for videnskaben nye arter. I dette bind 

 gives en faunistisk oversigt over samtlige paa expeditionen 

 tagne arter med oplysninger om deres horizontale og ver- 

 tikale udbredelse. 



Angaaende udbredelsen maa vi gjøre opraærksom paa 

 at mange forfattere ikke angiver, hvorvidt de har havt 

 levende eller døde exemplarer for sig. Vi er derfor ved 

 flere leiligheder i tvil om den horizontale eller den verti- 

 kale udbredelse er saa nøiagtig som ønskeligt, thi det er 

 ikke til dyrlevningernes udbredelse, men til det levende 

 dyrs at interessen særlig knytter sig. Flere nordiske arter 

 har saaledes vistnok faaet en altfor stor horizontal udbre- 

 delse; andre former staar derimod angivet med dybder, 

 som neppe kan gjælde levende exemplarer. Naar vi i det 

 Den norske Nordhavsexpedition: H. Friele & J. A. Grieg. 



The first volume of the Mollusca of the North At- 

 lantic Expedition treats of the Buccin/dcf. and the second 

 volume of the genus Bela, and some species that are either 

 rare or nevt' to science. In this volume. a faunistic survey 

 is given of all the species tåken during the expedition, 

 with information respecting their horizontal and vertical 

 distribution. 



With regard to the distribution, \ve must point out 

 that many authors do not state whether their specimens 

 Videre living or dead. On several occasions, therefore, vve 

 are in doubt as to whether the horizontal or the vertical 

 distribution is as exact as could be desired ; for it is not 

 to the distribution of animal remains, but to that of the 

 living animal, that special interest attaches. To several 

 Scandinavian species. far too wide a horizontal distribution 

 has thus certainly been assigned, while on the other hand, 

 other forms are given with depths that can scarcely apply 

 Jlollusea III. 



