404 BOTANICAL GAZETTE [ DECEMBER. 
almost always followed by death. It was further stated that the illus- 
trations of mushrooms intended for instruction should always be made 
under the direction of professional mycologists. 
Unification of methods employed in the determination of molds and 
yeasts.—To make comparable the diagnoses of these organisms, MM. 
Lutz and Guéguen presented a report which proposed that investiga- 
tors should substitute artificial culture media of definite and constant 
composition for natural culture media. 
Adoption of an international unit of micrometric measurement.—After 
an address by M. Mussat, the Congress urged all botanists to use the 
micrometric p. 
Periodicity of international congresses—It was decided that here- 
after international congresses should be held every five years and at 
different places. The Congress of 1905 was appointed for Vienna, 
with Professors Wiesner and von Wettstein in charge of the organiza- 
tion. 
NVomenclature.—The Congress declared itself incompetent to revise 
the laws of nomenclature, but it arranged for conference upon the 
subject among the principal botanical societies and establishments of 
different countries. A representative committee will be appointed to 
elaborate a plan to be discussed at the Congress of 1905. M. John 
Briquet, curator of the Delessert Herbarium, was asked to serve as a 
channel of communication among taxonomists interested in the solu- 
tion of the question of nomenclature, and to centralize all the corre- 
spondence. 
Phytogeographic nomenclature.—In view of the rapid extension of 
phytogeography, and at the suggestion of M. Flahault, the Congress 
voted that all ‘‘ geobotanists ” should be urged to come to an agree- 
ment in reference to the terminology of the general facts of phyto- 
geography ; and to establish in the principal languages the precise 
synonymy of the terms recommended for use by travelers and geog- 
raphers. 
Establishment of an international periodical for the publication of 
new botanical names.—The subject was presented by M. Hua, who 
showed the advantages of some authoritative list of new names, both 
in avoiding the multiplication of synonyms and in simplifying publi- 
cation. The Congress authorized M. Hua to devise a plan for realiz- 
ing this very difficult project. 
