JANUARY 20, 1923] 
NATURE 97 


Belgian Botany: a Record of War Time. 
HE Botanical Institute, close to the Botanic 
Gardens in Brussels, which bears the name 
of that distinguished Belgian botanist, Léo Errera, 
has resumed its activities since 
the war and is again under the 
guidance of Prof. Jean Massart 
of the University of Brussels. 
A large volume, Part 2 of 
vol. 10 of the collected papers 
of the Institute, has recently 
appeared, published in Brussels, 
with many plates, text-figures, 
charts, and maps, together 
with a list of the communica- 
tions published in the earlier 
volumes. Most of the papers 
have previously appeared in 
scientific journals in France 
or Belgium, but we note as 
apparently new contributions 
a brief note by Henri Micheels, 
comparing the effect upon 
seedling germination of the 
anions Cl and NO, and the 
cations K and Na, a note 
reporting the presence of cal- 
cium thiosulphate in Achro- 
matium oxaliferum Schew by 
Germaine Hannevart, and a 
continuation of phenological 
observations by E. Vander- 
linden, meteorologist to the 
Belgian Royal Meteorological 
Institute, which is lavishly 
illustrated by charts, and a 
description of the vegetation 
succeeding upon the war-time 
inundations of the Yser and 
upon the ruins of Nieuport. 
Prof. Massart’s earlier studies 
of the vegetation of the Belgian 
littoral make him the natural 
chronicler of the intense sub- 
sidiary struggle waged among 
the vegetation of this region 
and maintained long after the 
armistice of 1918. Behind the 
dunes bordering the Belgian 
coast there lies a long stretch 
of country, the level of which 
is intermediate between the 
level of the high and low tides 
of the sea. On October 20, 
1914, the Belgian engineers 
opened the locks at high tide 
and allowed the sea to flow 
over this portion of their front, 
thus preventing the farther 
advance of the German forces, 
and giving their own heroic 
troops a well-earned respite. 
For four long years these in- 
undations remained upon the 
land, fully maintained in winter 
by the natural rainfall and 
humid atmosphere, in the drier 
season assisted by the regulated 
influx of the sea controlled by the Belgian engineer 
service. Prof. Massart, aided by official photographs 
and maps, gives a vivid account of the effect of these 
conditions upon the vegetation, and, by further striking 
photographs of his own, records the rapid recovery 
NO. 2777, VOL. IIT] 

Fic. 2.—Same path in September 1920. 
of the vegetation of the region since the salt-water 
invasion finally ceased at the close of the war (Figs. 
I and 2). 

Fic. 1.—Raised footpath near Ramscapelle after retreat of floods, May 1919. Only vegetation, 
tufts of PAragmites communis in distance. 

Some of supports of original planking left, ground covered with 
Aster tripolium in flower, especially around shell holes on foreground on right. 
The vegetation of this region, once wrested from 
the sea, rapidly succumbed before the salt water— 
willows, poplars, elms, etc., all dying as the salt tide 
reached their roots. At Blankaert, where the waters 
of the Yser diluted the salt water, Massart figures 
