Review. 
264 
German frontier, of the “zinc plants” Viola lutea calaminaria , 
Alsine venia, Armeria elongata, and Thlaspi alpestre calaminare. 
These occur in great abundance on the old spoil heaps of zinc 
mines, and at the period of the visit (May 25th) were all in flower 
together, presenting a most beautiful sight. Asarum europceum in 
one of its few Belgian localities was afterwards seen. 
From these very brief notes some idea will be gained of the 
varied interest of the excursions, the arrangements for which were 
both simple and practical, so that no hitches of any kind occurred. 
They were all organised by M. Massart, who accompanied the party 
on every occasion, and was often assisted by other botanists with 
special local knowledge. M. Massart’s wide and thorough knowledge 
of Belgian vegetation, his indefatigable zeal in satisfying the visitors’ 
thirst for information, and his very great personal kindness and 
charm, combined to make him an ideal guide, and to render the 
excursions as enjoyable and instructive as they could possibly be. 
A short programme giving the essential features of the excursions 
and a number of outline maps, diagrams and sections illustrating 
the climate, geology, soil-relations and vegetation of the districts 
visited added greatly to the ease with which the features were 
understood. Mention should also be made of M. Massart’s magni¬ 
ficent “ Esquisse de la Vegetation de la Belgique” in two volumes, 
one of text and one containing a beautiful series of photographs, a 
copy of which was presented to every member of the Congress. 
The thoroughness with which the climate, geology and soils of 
Belgium have been studied greatly assists the student of its 
vegetation. 
REVIEW. 
“ Fossil Plants.” A Text-book for Students of Botany and Geology. By 
A. C. Seward, F.R.S. Vol. II with 265 Illustrations. Cambridge, at the 
University Press, 1910. Pp. XXII. and 624. Price 15/- 
We have waited a long time for the second volume of Professor 
Seward’s book, Vol. I of which appeared in 1898. The author says 
in his preface: “ Had Volume II been written ten years ago, the 
discoveries made in the course of the last decade would have given 
an out-of-date character to much of the subject-matter.” This is 
true ; fossil botany, just at present, is a subject in which books soon 
get superannuated. Still, we are glad to be assured that the author 
will not act on the same Fabian principle in the preparation of 
Vol. Ill which will be devoted to the Seed-plants. 
The present volume is chiefly occupied with the Lycopods and 
the Fern-like plants. The first chapter, however, (chap. XII of the 
whole book) completes the account of the Sphenophyllales, begun in 
Vol. I, by the description of Cheirostrobus and other types of 
fructification, more or less recently discovered. The question of the 
nature of the sporangiophore is shortly referred to, the author 
pointing out that if the leaf is in phylogenetic origin a “ branch- 
system of a primitive undifferentiated sporangium-bearing thallus ” 
(Tansley) ; our faith in the importance of such morphological 
discussions is shaken (p. 16). The question whether the differ¬ 
entiation of the sporangiophore was prior or subsequent to that of 
the leaf is, however, one which may still reasonably appeal to the 
morphologically inclined. 
In the short chapter on Psilotales (wisely treated as a distinct 
group) we are told that “ it is doubtful whether any useful purpose 
is served by retaining the genus Psilophyton ” (p. 29). This may 
