82 THE BOOK OF NATURE STUDY 



red ink ; trace the red-stained veins up the stalk into the leaflets. 

 Dip a leaf into hot water and notice the air-bubbles given off 

 by the lower surface, showing that this surface bears the stom- 

 ates. Note the difference (i) in colour, (2) in hairiness, between 

 the upper and lower sides of the leaf. Note the stickiness of 

 the ground-tissue of stem and leaf-stalk, due to gum which, 

 being retentive of water, prevents the tissue from drying up. 

 Note the difference in colour between the ground-tissue of the 

 stem (and the buried base of the leaf-stalk) and that of the leaf- 

 stalk (the part above the soil). Does the whitish ground-tissue 

 of the stem contain starch ? Test it with iodine solution. 



Examine plants month by month. The stem, buried in the 

 soil deeply enough to be safe from frost and drought, steadily 

 grows forward at the hair-covered tip, which occasionally forks 

 into two ; additional branches may arise from the buds on the 

 leaf -bases. The young leaf, like the growing stem-tips, is thickly 

 covered with hairs, which, besides acting as a protection against 

 cold and rain, may attract ants, which keep off caterpillars and 

 other destructive insects ; food material for new growth is stored 

 in the stem, and excessive loss of water is hindered by the gummy 

 sap of the soft tissue, which is very retentive of moisture. The 

 young leaf, which emerges in early spring, is at first curved at 

 the tip like a shepherd's crook, or like the young shoot of a 

 bean or pea seedling, and is well adapted for pushing up through 

 the soil. The coiled-up leaflets expand slowly, while the stalk 

 hardens, so as to withstand the strain imposed on it by the 

 spreading leaflets when they catch the wind. The expanding leaf 

 is symmetrical throughout, the parts unrolling successively in 

 pairs, so as to expose the leaflets to the air and light. When 

 bracken grows thickly, other plants are more or less completely 

 overshadowed and choked off. 



The bracken, then, has roots, stems, and leaves like a flowering 

 plant, but apparently no flowers or cones. Like other ferns, it 

 has no seeds, yet we know that new plants are produced. In a 

 fully grown plant, examined in late summer or in autumn, you 

 will notice that the edge of each leaflet is turned in towards the 

 underside, and is fringed with a scaly strip which covers a groove 

 .filled with brown grains. These are so abundant that the edges 



