254 JOUENAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Meadow Formations and the Steppe Period in Alsace. By 



Prof. Ernst H. L. Krause (Bot. Zeit. Ixvii. Abt. 1, Heft viii./ix. Aug. 

 1909, pp. 141-173).— The oecology of the Vosges mountains and of the 

 valleys from Basel to Strassburg is described. The author finds that 

 there are two formations: first, what he classes as heath, which is 

 characterized by Calluna and Vaccinium (including Nardus association) ; 

 and, secondly, a less uniform meadow formation (Wiesen) which merges 

 into Phragmites and other reed associations in wet places, and in drier 

 situations becomes a " HartfeU " or " Hartheath," characterized by 

 Andropogon ischaemum. 



Nehring's hypothesis of a Steppe period during the Pleistocene, at 

 which time a continuous Steppe, with the characteristic plants and 

 animals, is supposed to have extended from the Black Sea to Upper 

 Germany and France, is severely criticized by the author. There is no 

 proof that the climate of that time was either warmer or drier than it is 

 in the same districts to-day, although it may certainly have been warmer 

 and drier than in the glacial epochs which preceded it. Even now the 

 author shows that there is not so very much difference between the 

 climate of the Black Sea Steppes and that of the district alluded to. 

 Such plants as Stipa pennata, Eryngium campestre, &c., which occur 

 in Alsace, are not necessarily, though they may be, relicts of a Steppe 

 flora. 



The vegetation of the supposed Steppe period would be a transitional 

 stage between the tundra-like fields of the Arctic regions and the 

 Northern forests. 



Then he thinks that woods spread over almost the whole country, 

 though it could not be absolutely continuous forest, for there would 

 always be open spaces due to local climatic or physical causes (rock, 

 altitude, &c.). 



Man seems to have appeared in Upper Germany at least four thousand 

 years before any botanical examination of the flora was carried out. 

 But numerous American plants are firmly established in Europe after 

 only a few hundred years, so that he considers that the supposed 

 Steppe relicts may either have been introduced or spread naturally 

 from the Black Sea region during this long period, or may even have 

 lived on in the forest clearings and open spaces. There is no proof, 

 in his opinion, that a continuous Steppe extended from the Black Sea 

 to Upper Germany. 



Briquet's Xerothermic period belongs to the last Palaeolithic age 

 (La Madeleine), and the warm period in Sweden (Gunnar Andersen) 

 belongs to the Neolithic age, when man had already settled in Alsace. 



A great number of species occur to-day both in the " Black Earth 

 districts of Eussia and in Alsace, and Steppe species are found in wooded 

 districts much colder than Germany. 



The differences in the flora of the Eussian Steppes and Alsace are 

 explained as due partly to the colder winters of the Steppes, but espe- 

 cially because the salt found in the soil does not exist in Germany. 

 The meadow formations of Alsace are derived from freshwater marsh 

 and the grasslands of the Black Earth, or from salt swamps. 



