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THE PLANT WORLD. 
Professor Goebel took up the study of morphology as correlated 
to function and environment. He has given us in his Organo¬ 
graphy of Plants and his Pdanzenbiolo gische Schil derun gen an 
accurate determination of facts and factors upon which many 
previous students had wasted much time and ink in specu¬ 
lation. Goebel put spirit and life into the dry bones of anatomy 
as studied by de Bary and Schwendener. The experimental mor¬ 
phology which he has opened up must be the solution of many 
future ecological problems. 
In France we have seen that a Phytogeography of Europe was 
published in 1855 by Alphonse De Candolle. In 1878 Vesque 
began the publication of his investigations upon the influence 
of environment upon the form of the plant. About the same 
time, Bonnier began his valuable studies on Alpine plants, and 
later worked in conjunction with Flahault who has given particu¬ 
lar attention to the physical factors of the environment. The 
work of Constantin which began in 1883 is along a similar line. 
Jaccard, of Lausanne, Switzerland, may also be included in this 
list of French ecologists, because his methods and work are 
largely the same as theirs. 
For many years the Scandinavian botanists have studied plants 
in their relation to environment and have given us some of the 
most valuable information we possess concerning the plants of 
northern Europe. It may be noted that they have studied the 
ecology of the algae and their distribution in the plankton. This 
calls attention to the fact that, strange to say, almost all ecological 
studies have been upon the higher plants. There is unquestion¬ 
ably a rich field for study in the lower plants, and especially 
among the fungi, in the investigation of such topics as the 
penetration of host plants by parasites, the relation of saprophytic 
fungi to the nature of the substratum, the ecology of facultative 
parasites and saprophytes, etc. 
We owe to Professor Warming, of Copenhagen, more than to 
any other, the conception of the plant society; an idea implying 
the existence of an organic unity among the plants. In his 
Text-Book of Ecology he took up and worked out the classifica¬ 
tion of plant societies according to the water content of the 
