40 THE VEGETABLE KINGDOM. 



tumbler, and keeping it moist, warm, and shaded. In a 

 short time a thin green film will spread over the soil, which 

 take up carefully on the point of a lancet, and examine 

 under the microscope. The little spore first becomes 

 swollen, angular, and bursts, throwing out a fine rootlet, 

 which fixes in the soil and draws in nourishment. Then a 

 number of delicate transparent cells are formed from the 

 mother-cell in the spore, making a little green scale, which 

 as it expands throws out many fibres or rootlets on the 

 underside. The wonderful part is that this tiny green 

 scale produces two kinds of cells, which fructify each 

 other, as do the stamens and pistil of flowering plants. 



One set of cells, called antheridia, contain most curious 

 spiral filaments, which move spontaneously, and wheel 

 round and round until the cell breaks, and they escape 

 to enter into the other kind of cells, called archegonia, or 

 germ -cells, from which the real stem of the future fern is 

 produced. This is difficult to watch, and it requires a 

 power of 300 diameters to see these moving filaments, 

 called antherozoides ; but the development of the little fern 

 is in itself worth seeing and mounting for the microscope 

 in its several stages. 



Eerns are amongst the flowerless plants, very numerous, 

 very useful; not fewer than 2000 species inhabit various 

 parts of the world, from the tall Tree-fern of the tropics, 

 more than fifty feet high, to the humble Spleenwort 

 (Asplenium ruta-murarid) which haunts our ruined walls. 

 Their claim to usefulness rests on their medicinal pro- 

 perties ; the thick mucilage from Adiantum capillus Veneris 

 being a famous cough nostrum ; a decoction of Poly podium 

 is taken as an anti-rheumatic and sudorific beverage; 

 Osmunda regalis is given to rickety children as a tonic; 

 and others are used as styptics and purgatives. The roots, 

 when roasted and peeled, are eaten by the natives of New 

 Zealand as we eat bread. 



Moore's ' Handbook of British Ferns ' is a most useful 

 companion in a country walk, to assist us in recognising 

 the different species. 



