Schimper used the term xerophytes to include plants which live in soils which are physiologically dry, and the term hygrophytes those which live in soils which are physiologically wet or damp. Schimper recognized that the two classes are connected by transitional forms, and that it is useless to attempt to give the matter a statistical basis.
Whilst Schimper objected to the constitution of a special category, such as mesophytes, to include all plants which are neither pronounced xerophytes nor pronounced hygrophytes, he recognized the necessity of a third class in which to place those Schuuw, Grundtraek til en almindelig Plantegeografie (Kjbbenhavn, 1822); German trans., Grundzuge einer allegemeinen Pflanzengeographie (Berlin, I 823).
I Schimper, Pfianzengeographie auf physiologischer Grundlage (Berlin.
(53 mm.) (Schimper, 1903: 606).
Cold Temperate and Frigid Districts.In the coldest portion of the north temperate zone, forests of dwarfed trees occur, and these occasionally spread into the Arctic region itself (Schimper, 1904: 685).
Schimper distinguishes moss tundra, Pot ytrichum tundra, and lichen tundra; and the lichen tundra is subdivided into Cladonia tundra, Platysma tundra, and Alectoria heath.
For example, Schimper, after describing the scierophyllous woodland of the Mediterranean district and of the Cape district, says:
Schimper had previously maintained that the action of common salt in the cell-sap is detrimental as regards assimilation.
It is sometimes maintained, for example, by Schimper, that their xerophytic characters are related to the physiological dryness of the habitat: this, however, is denied by others who maintain (Clements, 1905: 127) that the xerophytism is due to the persistence of ancestral structures.
Schimper (1903: 102) thinks that in the case of aquatic plants, the difference must depend on the amount of lime in the water, for the physical nature of the substratum is the same in each case.
Xiv.; Schimper, Sur lAmidon at les Leucites, Ann.
Schimper, Plant-Geography (Clarendon Press, Oxford); Goebel, Organography (Clarendon Press, Oxford); Bower, The Origin of a Land-Flora (Macmillan); Beyerinck, Ueher Cecidien, (Bot.
We may agree with Schimper that such a point of view is obsolete without rejecting as valueless the admirable accumulation of data of which it admittedly fails to give any rational explanation.
We arrive thus at the essential aim of geographical botany, which, as stated by Schimper, is an inquiry into the causes of differences existing among the various floras.
Schimper, Plant Geography, transl.
For geology, Schimper, in the Zeitschrift der Gesellschaft fiir Erdkunde (Berlin, 1869).
P. Schimper advanced this department of science.