1895. | Development of Botany in Germany. 251 
the other hand, the great excellences of the work were, that 
it gave for the first time a coherent presentation of the veg- 
etable covering of the earth, that it divided the various floral 
territories into formations, and that it described the charac- 
teristic plants of each territory and formation. The later 
works of German investigators into the geographical distribu- 
tion of plants, in contrast to those of Grisebach, are based on 
the theory of transformation, which here as elsewhere has 
shown itself to be extraordinarily fruitful. At the same time, 
the subject became divided into what may be called the geo- 
logical or developmental, the systematic, and the biological 
sections. These do not antagonize one another but, on 
the contrary, supplement each other in giving a many-sided 
yet harmonious treatment of the whole. 
The most important work in the geological section is by 
ENGLER (Kiel, Breslau, Berlin), published in two volumes in 
1879 and 1882, under the title ‘Versuch einer Entwick- 
lung der Pflanzenwelt.” In contrast to Grisebach, the author 
the explanation of many phenomena of distribution which 
cannot be accounted for by the present climatic condi- 
tions alone. The purely systematic direction, which con- 
cerns itself with the present conditions of the geographical 
distribution of plants, and seeks to define the limits of the 
floral kingdom, to mark the areas of species, is cultivated 
mainly in the Botanical Museum at Berlin, which contains the 
richest herbarium in Germany. Through the activity of our 
explorers and colonial officials, a mass of material, rich in 
African species, has been gathered together in recent years, 
which is now being worked up by Engler, with the assistance 
of other experienced botanists. The results up to this time 
