Botany and Zoology. 



allied but more or less distinct varieties, or even species, who: 

 limits overlap, and whose members, very probably, occasiona 

 then" A further advantage claimed for this hypothesis is, 

 a fact brought out by Dr. Hooker in a former publication, 

 Scandinavian flora is present in every latitude of the globe, ! 



Moreover, Dr. Hooker discovers in the flora of Greenland a 

 explicable upon this hypothesis, but hardly by any other, viz. : 

 plete identity with that of Lapland ; its general paucity, as we 

 in peculiar species ; the rarity of American species there ; 



't Greenland and Scandinavian species in enormously remote alpine lo^ 

 of West America and the United States. Our author reasons thus: 

 5 granted that the polar area was once occupied by the Scandinai 

 , and that the cold of the glacial epoch did drive this vegetation soi 

 Is, it is evident that the Greenland individuals, from being confined t 

 asula, would have been exposed to very different conditions from those 

 "°"* .:-—.- In Greenland many sp ■ '" -"^ *^" '''' 



portion of the peninsula, and, not being there brought into competition 

 struggle for '" ^ ^ " -= " 



linated ; and the survivors would 

 there broug 



• life amongst their progeny, 

 and, consequently, no selection of better^adapted varieties. On the return of 

 heat survivors would simply travel northivards, unaccompanied by the plants 



The rustic denizens of Greenland, huddled npon the point of the peninsula 

 dunng the long glacial cold, have never enjoyed the advantages of foreign 

 travel; those of the adjacent continents on either side have 'seen the world,' 

 and gained much improvement and diversity thereby. Considering the present 

 Jngid cHmate of Greenland, the isotherm of 32^^ just impinging upon its 

 «!l u P*'^"*' it^ moderate summer and low autumnal temperature, we should 

 rather have supposed the complete extermination of the Greenland ante-glacial 

 "ora; and have referred the Scandinavian character of tiie existing flora (all 

 out eleven of the 207 arctic species, and almost all those of temperate Green- 

 land, being European plants,) directly to subsequent immigration from the 

 eastern continent. Several geographical considerations, and the course of the 

 cotrents, which Dr. Hooker brings to view on p. 270, would go far towards ex- 

 Plaimng why Greenland should have been re-peopled from the Old rather than 

 ^ni the New World. While the list (on p. 272, 273) of upwards of 230 Arctic- 

 European species which are all likewise American plants, but are remarkable 

 for their absence from Greenland, would indicate no small difficulty m the 

 -stvard migration, and render it most probable that the ditfiision of species 

 ^™m the Old world to the New was eastward through Asia, for the ardtc no 

 ■ ^^^n (as has elsewhere been shown) for the temptrate plants. Was it that 

 «id and the adjacent part of the American continent remained glacial 

 "•'lan the rest of the zone ? And if our northern regions were thus colo- 

 - y an ancient Scandinavian flora, this seems to have been in return tor 

 ^■■iHier donation of American plants to Europe, to which a very lew ex- 

 ^S t)ut numerous fossil remains bear testimony. SpecuUt 

 fruitfut^ ^^ enticing, and the time is approaching m v - 



Indeed, the characteristic features and the immediate interest and import- 

 ance of the present memoir as of others of the same general scope and mter- 

 "^^■^ are fo„nd in thi^^: 1. That the actual geographic'al distribution of species 

 ■'V? to be accounted for; 2. That our" existing species, or their origi- 

 ^^r more ancient than was formerly thought, mainly if not ^holly 

 '-' the Glacial period: and, 3. That they have therefore been subject 

 ^^limatrc vicissitudes and changes. There may be many natnralista 

 - 'U',. Sci.— SEcovn Rai.™*. Vol. XXXIV, Xo. lOO.-JrLT, 1S02. 



1 which tliey may 1 



