THE WOODS IN AUTUMN 239 



whenever moisture is not altogether absent. Even light, 

 although necessary for all green plants, is not absolutely 

 needed for mushrooms and those animals which have be- 

 come adapted to living in caves or in the absolutely dark 

 abyss of the ocean. It is true that in the dense shade of 

 thick woods, farmers cannot raise potatoes, wheat, or corn, 

 nor would we look in such places for sunflowers and golden- 

 rods, for all these plants love the bright sunlight. If, how- 

 ever, we wish to find the delicate fronds of the maidenhair 

 fern or the pigmies among land plants, the mosses or the 

 gray and ever old-looking lichens, then the shady woods are 

 the very places to go to. 



49. Ferns and Horsetails. 



MATERIAL : As many different kinds of ferns as you can find. With 

 a stout knife or with a hatchet dig up the creeping rootstock of the 

 species you find. Names of species are of little importance to your 

 pupils. Fruiting and sterile horsetails. 



Among the most common and best-known ferns are the 

 Brake, or Bracken (Pteris aquilina), the Maidenhair Fern 

 (Adiantum pedatum), and Clayton's Fern (Osmunda Clay- 

 tonid). 



The last mentioned is very common in moist places. In 

 the vicinity of St. Paul it grows abundantly around the 

 numerous ponds in the oak woods. On the fertile leaves 

 some of the leaflets are entirely converted into spore cases. 

 These spore cases contain a green dust, the spores. When 

 the spores are ripe and fall out of the spherical cases, scat- 

 ter a little of the dust on moist earth in a small flower pot, 

 then cover the soil with an inverted drinking glass and keep 

 it moist, but not wet. Very soon the earth, which should be 

 somewhat firmly packed, will appear more or less green on 

 account of a large number of minute heart-shaped plants 



Visit a sawmill and a lumber-yard. 



