The Fern Alliance 
But the reader must be referred especially to the 
“ Annals of Botany,” where the discoveries of Dr. Scott, 
Professor Oliver, Mr. Arber, and mariy others are given 
in the original. 
In the comparatively quite modern Jurassic period, 
which has been so thoroughly studied by Seward and 
others, the most interesting point is the extraordinary 
uniformity of the flora wherever its remains have been 
discovered. Plants of the very far South, such as those 
described from Louis-Philippe Land, 63° 15’ S., from 
Greenland, from temperate Europe, and from the tropics, 
seem to have a remarkable similarity in appearance, 
which shows either that the climates of the world or 
that its vegetation had not specialised or become so 
diversified as they are in our own days.” 
The ferns of to-day are by no means confined 
altogether to still, moist atmospheres, though it is in 
such a climate that they seem to luxuriate. 
Our common bracken is one of the most cosmo- 
politan of plants, found almost all over the world, but 
usually at least on poor soil. In the Scottish lowlands 
and highlands it is a dangerous pest, for it spreads over 
sheep pastures and heather moors. Some practical 
method of exterminating it has yet to be discovered. 
If for two or three years it is mown three or four 
times over in a season it is said to vanish, but that is 
far too expensive a process. 
Sheep will not eat it, nor is there even a beetle or 
insect which seems able to browse upon it. But it is 
said that, in Japan, the bracken is really eaten and 
enjoyed by the labouring classes. If it were possible 
to recommend its use as food for man the question 
would indeed be solved, but the author does not wish 
to be guilty of any person’s death or even of “un 
mauvais digestion,’ so he must admit that when he 
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