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 many 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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