No. 489] NOTES AND LITERATURE 



601 



BOTANY 



Plant Geography.— The Scamlimivian fiom. Several naturalistic 

 have considered tlie origin of the biota of the Scandinavian peninsula. 

 During the glacial period most of the higher forms of life must have 

 disappeared, leaving the peninsula to be repopulated by immigrants 

 from other regions as the ice receded. This immigration was early 

 thought to have had two sources: the central European lowlands and 

 the Russo-Siberian region. The biota of the former is supposed to 

 have come in by wav ot one or more Baltic land connections, and that 

 of the latter is thought to have gained access by way of Finland and 

 northwestern Russia. But besides these a third element, called bv 

 Blytt "the Atlantic group" ot plants, was discerned, as the flora, especi- 

 ally of the western part, became better known. 



This so-called "Altantic" element is discussed bv Stejneger (Swith. 

 Misc Coll (,nnt ■! 4-.S--)l ^ ]')()7) hoin both th( /oologi. il an<l 



mnUun in Noiu u .vpt .l..n^ tlx c .i Imiumii .n i .n.l 

 Krlstlcln.sundor^^lur( tlu ^ m u Ik slumnfluxt iKuidtinMl l,..ni 

 this secondary center of distribution. 1 Ins associatiim shows a sironii 

 resemblance to the biota of Scotland and noriliwcstcni Ireland, and 

 Stejneger thinks that the similaritv is not dur to parallel drvelopiiiciii 

 but that It ukIk n.s . dii((ti^(n<li( (onn.Mion I.uumm tli. luo 11,. 



