1895. | Development of Botany in Germany. 201 
development of various groups of alge, and of the alga-like 
Saprolegnie followed in subsequent years. Other valuable 
researches by Ferdinand Cohn,de Bary, PFITZER (Heidelberg), 
Goebel, Berthold, Fr. Schmitz, Reinke, and other German 
investigators supplemented them, but in 1869 Pringsheim 
made another remarkable contribution to this field of knowl- 
edge by his discovery of the copulation of gametes (zoospores). 
Early in the sixties the impulse to a reform in the study of 
the Fungi was given by de Bary in Germany, while Tulasne 
had already done the same in France. It was de Bary who, 
more than any one else, perfected the methods of investi- 
gating the Fungi, directed researches into decisive lines, and 
laid the foundations for the results which this department of 
knowledge was soon able to show. After him O. BREFELD 
(Miinster) took the lead by his achievements in this field, and 
since 1872 has devoted himself to studying the development 
of fungi, beginning with a single spore and tracing its de- 
velopment to the end.  Brefeld’s methods, extended and 
adapted to the field of bacteriology, have produced great 
results. De Bary first effected the artificial infection of a host 
by a fungous parasite, but Brefeld was the first to succeed in 
cultivating typical parasites in nutrient solutions, thus making 
them saprophytic. By de Bary’s investigations, our notions 
of the alternation of generations among the Fungi were brought 
within the true limits, while Brefeld leveled the ground for 
the construction of a natural classification of the Fungi, and 
considerably limited the statements as to sexual differentiation 
in this group. 
The demonstration of the fact that lichens are symbiotic 
double organisms, depending upon the union of ascomycetous 
(rarely hymenomycetous) fungi with alga, attracted general 
attention. In 1860 and 1868, in the first two parts of his re- 
searches into the lichen thallus, Schwendener declared the 
gonidia to be the terminal cells of short lateral branches of 
the hyphe. In 1866 de Bary led up to the true idea of the 
lichen thallus in the gelatinous lichens, and spoke the words 
which solved the whole problem and brought about the right 
conception of all lichens. This final step was taken by 
hwendener in the supplement to the last part of his ‘‘Flecht- 
€nstudien, ’and was repeated still more decisively in his ‘‘Algen- 
typen der Flechtengonidien,” published in 1869. In basing this 
conception on studies in development, STAHL (of Jena) has 
