Plant Study. 757 



with our own ferns, the part bearing the fronds is at the growing tip, and 

 the rootstock of the past years instead of dying stands as a trunk for 

 the tree fern. 



If we were to study the story of one of our Christmas ferns we 

 should begin before mid-summer. Then we would find in our fern clump 

 several fronds which have the leaflets toward the tip considerably smaller 

 than the others ; and we would find on the lower side of these leaflets 

 what would seem at first like rows of pale blisters. Later these blistery- 

 looking spots would turn brown and if looked at with a lens would show 

 a depression in the center. Later the edges of each little brown disc 

 would be pushed up by some tiny masses of round, brownish bodies not 

 larger than pin points. These push out in such profusion that they make 

 the complete lower side of each leaflet look brown and fuzzy (Fig. i.i). 



If we examine under a strong lens or a microscope just one of 

 these little globular grains, we will find it to be a very strong little 

 mechanism for the protection and distributing of " fern dust " or spores ; 

 it is a spore-case nearly globular in form, and it has a little stalk which 

 fastens it to the fern leaf (Fig. 1.3). Continuing as a part of the stalk 

 around the edge of the spore-case is a thicker portion divided into seg- 

 ments ; this does not reach completely around. When the spores are 

 ready to be scattered, this stiff part acts like a spring and straightens out 

 tearing apart the spore-case and setting the spores free (Fig. 1.4). The 

 spores or ** fern dust " are brown bodies, so very small that we can see 

 them only when they fall in masses, and then they look like dust. If any 

 fern in the fruiting stage be laid upon a sheet of white paper with the 

 lower side next to the paper and left there out of a draught for a day 

 or so and then taken up, its exact form will be left on the paper outlined 

 in this " dust ;" that is, the spores will fall on the paper from every part 

 of the fern leaves, and thus make a picture of the fern. Some people 

 call these little spores the seeds of ferns, but this is not true any more 

 than that the pupa of a moth in the cocoon in which it passes the winter 

 is the egg of the moth. The spores of a fern will retain their vitality 

 for a long time, and if they do not find conditions favorable for their 

 growth when they are shed, they wait until such conditions come and 

 then grow; thus the spores constitute a stage of fern-life which may be 

 called a " waiting " stage. When a spore finds dampness and warmth it 

 begins to grow and first develops a tiny, rounded leaf which does not 

 in any respect resemble a fern ; this little, leaf-like structure develops 

 rootlets at one side and also on its lower surface two kinds of pockets. 



