THE ORIGIN OF THE SO-CALLED ATLANTIC ANIMALS 
AND PLANTS OF WESTERN NORWAY 
By LEONHARD STEJNEGER 
CoNTENTS 
PAGE 
kL. Jnteodaction e300 Sance w eo ae ee ee eee 458 
Tl. Phe Red Dede: 2a arenas 3 yan eink oe eee ee ee eee 462 
TEL... Phe. Celtic: #lorse 3c faves isons hes os lo eee ee ae 469 
LV; Other Species of Manimals yii0500 3... s 2-0 ec ee cee ee ee 
Vo Two Atlantic 7. Species ob Bitds.. 25a. eee itis Bee eee 480 
VI. The “Atlantic” and “ Arctatlantic”” Plants of Western Norway.. 484 
VII. The Way of Dispersal into Western Norway.................... 487 
Vil ‘The “ Subatlantie*y Biota: Soo seat eis sete ye orale ere epee ace renee 496 
IX. A Sketch of the Geological Considerations Involved............. 497 
XP Siritiaty one oon ce cee re eee eee eas ere 512 
I. INTRODUCTION 
The present essay is an attempt to account for the existence in 
western Norway of a complex association of plants and terrestrial 
animals not found elsewhere in Norway except as manifest peri- 
pheral radiations from a secondary center. of distribution, which 
embraces the coast between Stavanger and Kristianssund.t These 
animals and plants display an unmistakable relation to a similar 
biota strongly developed more particularly in Scotland and north- 
western Ireland, and it is here proposed to examine a little closer 
into this relation with a view to ascertain whether the connection 
is direct and genetic, or only indirect and due to parallel develop- 
ment. Because of the insufficiency of the material at hand as well 
as the unsatisfactory status of the scientific record, the inquiry only 
relates to a few selected forms and is primarily undertaken to serve 
as a foundation for a theory as to the origin of the biota which has 
received the somewhat unfortunate appellation “ Atlantic”? and to 
1This stretch of the coast of Norway has no convenient distinctive name 
of its own. The Norwegian word “ Vestenfjelds” is not exclusive enough, 
nor is “ Vestlandet,” both terms embracing much more of the country to the 
south of Stavanger as well as the interior fjord districts east to the watershed. 
It is often called “the northwestern fjord district,” but “northwestern” is 
to some extent misleading and the term is cumbersome. In this paper when 
speaking of “ west Norway” and “western Norway” I mean this coast strip 
between Buknfjord, in the south, and Trondhjemsfjord, in the north, or 
roughly between 59° and 63° north latitude. 
