262 
The Brussels Congress of Botanists. 
of the relations of plants and plant-communities with the environ¬ 
ment {milieu). 
All of these recommendations were voted upon by raising the 
hand, and were carried nernine contradicente. 
The Reporters also stated that they had found there was general 
agreement on the following proposition:—The plant association 
represents a definite entity in vegetation, while the plant-formation 
is something different. This proposition was not put to the vote. 
It may, however, be said that there is almost complete unanimity 
on the proposition that the plant-association is a unit of definite 
floristic composition, while the plant-formation represents a unit of 
a higher category. 
It is to be regretted that no agreement was reached on the 
terminology relating to altitudinal belts or zones of vegetation. 
The Reporters proposed to restrict the word zone to the great 
climatic zones of the earth as a whole, to adopt the terms belt, 
stage, Stufe for altitudinal “ zones,” and to introduce the terms girdle, 
ceinture, Giivtel for other “zoned” arrangements of vegetation. 
They recommended that the term region should be confined to exten¬ 
sive stretches of country. Prof. Engler opposed this last recom¬ 
mendation on the ground that “ region ” in the sense of “altitudinal 
zone” has been used in innumerable phytogeographical descriptions. 
Some workers may be disappointed with the comparatively slight 
progress that has been made towards settlement of the important 
questions dealt with in the “ Report.” It must, however, be 
remembered that while the section of taxonomic nomenclature has 
to deal with rules which necessarily have a purely arbitrary 
foundation, and are adopted for the sake of practical convenience, 
the task of the phytogeographical section is quite different. Phyto¬ 
geographical nomenclature deals with the concepts which form the 
basis of this branch of the science, and the task set to the Reporters 
was to find out how far general agreement prevailed as to these 
concepts. It is useless to recommend the general adoption of terms 
corresponding to the concepts, unless general agreement prevails as 
to the concepts themselves. It is evident that in the present state 
of phytogeography we have not quite reached such a general 
agreement, and this is not to be wondered at when we consider the 
unexampled difficulty of properly determining concepts relating to 
the varied and constantly changing groupings of vegetation. 
Meanwhile the thorough ventilation of the questions and the 
interchange of ideas that has taken place will be of the greatest 
possible benefit to the science, and the very greatest credit is due 
to the Reporters for the immense pains they have devoted to the 
subject, for their able summary of their own views, for bringing 
together the most important opposing views, for their invariable 
courtesy and moderation and generally for the statesmanlike manner 
in which they have dealt with the whole problem. 
Excursions. 
The excursions organised by Professor Jean Massart were not, 
for the most part, attended by very large numbers of congressists, 
doubtless because many of them took place while the Congress was 
sitting, but those who did attend found them both extremely 
pleasant and very profitable. 
The first excursion, lasting two days, May 12th to 14th, before 
the Congress, was to the Belgian littoral, where the magnificent 
