340 FUNARIA. 



the peristome downwards, and note that just above the 

 upper limit of the air-space there is 



(j) a rim consisting of two or three layers of cells 

 which are elongated radially and have pitted walls. These 

 layers of cells join the peristome to the epidermis of the 

 capsule-wall, reaching the latter at the constriction which 

 separates the operculum from the rest of the capsule. 

 When the operculum is detached, the layers form the rim 

 of the open capsule. Just above this rim tissue is 



(&) the annulus, consisting of about five superposed 

 layers of epidermal cells, distinguished from the general 

 epidermis by their greater radial depth ; the upper annulus 

 cells are narrow and thick-walled, but the two lowest layers 

 (the annulus proper) have thinner walls and are swollen. 



476. Stomata on the Apophysis (Fig. 83). Cut tan- 

 gential sections from the surface, and note that although 

 each stoma is formed in the usual way by division of an 

 epidermal cell and splitting of the division-wall the two 

 guard-cells have joined at their ends, so that the mature 

 stoma is surrounded by a single continuous guard-cell. 



477. T. S. of Capsule. Examine transverse sec- 

 tions taken at different levels through capsules of different 

 ages, and compare the structures with the description in 



475. 



478. The Capsule as Assimilating Organ. That the 

 capsule of Funaria is well adapted for carrying on photosynthesis 

 can be shown by steeping a number of unripe capsules in alcohol 

 in a corked tube, and comparing the depth of the colour of the 

 extracted chlorophyll with that obtained on placing pieces of the 

 foliage-leaf of a flowering-plant, e.g. Sunflower or Nasturtium, in 

 an equal quantity of alcohol in another tube. A Funaria capsule 

 contains as much chlorophyll as about fourteen Funaria leaves, 

 and in this respect is equal to nearly 5 square mm. of a Sunflower 

 leaf, and more than equal to the chlorophyll-content of the rest 

 of a well -grown leafy Funaria shoot. 



479. Frotonema, Buds, Bulbils. Sow spores from 

 ripe capsules on moist soil, bricks, or tiles, kept under a 

 bell-glass, and note that after a few days green threads 



