65 
“The Character and Operation of the Potato Disease,” illustrated 
by diagrams and specimens. 
Dr. Masters treated of “The Production of Varieties by Cul- 
tivation,” and explained the processes. 
In the subsequent discussion a number of prominent gar- 
deners took part. : 
On the Cultivation of the Fresh-Water Alge. In the Report 
and Transactions of the Penzance Natural History and Antiqua- 
rian Society for 1885-86, Mr. J. Bernard Magor has an interest- 
ing paper on this subject. He remarks :—‘ The statement that 
the home-growth of Alge enables their development to be 
studied carries with it its own justification. In these days the 
influence of the study of development in biological work of any 
kind is evident, and the importance of that study is attested by 
the constant succession of memoirs that are published, dealing 
with the development of all manner of:creatures. Valuable in- 
formation may be got in three ways from the cultivation of the 
Alge: 1. The identification of species not at first noticed in the 
gathering. 2. The observation of various stages of development, 
and the elucidation thereby of the successive phases of the life 
history of a species. 3. The determination of the effects pro- 
duced on any given species by changes in the conditions of its 
growth.” 
The development of Chetophora pisiformis is then described. 
It is stated that all authorities say that it is devoid of bristles, 
whereas, according to his experience, the young, shooting 
branches nearly all end in bristles. Oscéllaria princeps was also 
studied, and some very curious phases. of its growth were 
noted. 
A Method for Retaining the Color of Plants Preserved in 
Alcohol. (Berichte der Deutschen Botanischen Gesellschaft, iv., 
No. 8.) Dr. Tschirch has discovered that tannates and coloring 
matters of plants, with the exception of Xanthophyll, form com- 
pounds with lead and barium which are insoluble in alcohol; 
therefore, he recommends the specimens to be put into solutions 
of compounds of lead or barium before transferring them to 
spirit, or simply to add concentrated solutions of acetate or nitrate 
. 
