304 



SPOROPHYTE OF THE BRYALES 



reservoirs (Fig. 206, D}. During drought, this delicate apparatus 

 is protected by the coiling of the leaves into needle-like rolls 

 which result in the exposure only of the thickened epidermal cells. 

 The sexual organs are developed on the apices of the main or 

 lateral branches and they are protected by modified leaves which 

 are often colored and form a more or less conspicuous bud or 

 cup (Fig. 207, i). This is especially true of the antheridial 

 buds, the plants being monoecious or dioecious. The antheridia 

 and archegonia are essentially of the same structure as noted in 



FIG. 209. Germination of the gametospore: 10, base of the archegonium 

 in which the gametospore has germinated, forming a mass of cells with apical 

 growing cell, x. II, later growth of the gametospore. The sporophyte, 

 spr, still enveloped by the archegonium, ar, appears as a cylindrical mass 

 of cells with foot, b, penetrating the stem of the moss plant. At right an 

 unfertilized archegonium. See Fig. 205, B. After Sachs. 



previous groups and they are usually associated with modified 

 leaves known as paraphyses (Figs. 207, 6; 208). The germina- 

 tion of the gametospore and the development of the sporophyte, 

 while presenting many features in common with the hepatics 

 and Anthoceros in particular, shows a remarkable series of varia- 

 tions that are of decided advantage to the plant. The gameto- 

 spore in its early growth forms a spindle-shaped mass of cells, 



