122 



NATURE STUDY 



them, prothallia can 

 be raised in the school- 

 room and ferns grown 

 from the prothallia. 

 This will prove very 

 interesting and in- 

 structive. 



The spores may be 

 'collected by placing 

 the spore-b earing 

 leaves on sheets of 

 paper, and letting 

 the leaves dry, when 

 the spores will be dis- 

 charged, covering the 

 paper as a fine, brown 



, T/ , ,. Fie. 76. A single spore-bearing organ of a fern highly 



pOWder. If the Spores magnified. Taken from one of the dots shown in fig. 75. At 

 . , S is a spore escaping. 



are sown on fine,rather 



closely-packed earth, and kept moist, and covered with glass 

 BO as to prevent evaporation, a fine green, moss-like growth 

 will make its appearance in a week or two, and by the end 

 of five or six weeks, the little flat, heart-shaped plants spoken of 

 before as the first stage will appear. They are of a dark green 

 color, and are the prothallia. These prothallia are attached to 

 the ground by fine root-hairs. Very soon we may find growing from 

 the under side of some of the larger of these little plants the fern 

 as we know it. It is attached to the ground as well as to the pro- 

 thallium (fig. 78). As the plant grows, the prothallium dies, leav- 

 ing the fern as an independent plant, which afterwards bears 

 the spores. 



The reproductive organs are on the under-side of the prothal- 

 lium as shown in figure 77. These can be readily made out with a 

 hand lens if the pupils are old enough to appreciate this work. 



