VI. THE BRYALES 199 



ment of the cells in different individuals in the same inflor- 

 escence. 



The ripe antheridium opens promptly when placed in water. 

 At the apex there is usually present a single cell decidedly 

 larger than its neighbours (Fig. 103, A), or sometimes there 

 are two opercular cells (Goel)el {22), p. 239). All of the 

 parietal cells become strongly turgescent and this is especiallv 

 the case in the terminal cell, which finally bursts and forms a 

 narrow opening through which the mass of sperm-cells is forced 

 out by the pressure of the distended parietal cells, and the swell- 

 ing of the mucilage derived from the disintegration of the walls 

 of the sperm-cells. The opercular cell in Fiinaria is not de- 

 stroyed, as a rule, and is still very conspicuous after the sperm- 

 cells have been discharged, so that the empty antheridium, ex- 

 cept for a slight contraction of its lower part, looks very much 

 as it did before the escape of the sperm-cells. In some other 

 Mosses, e. g.^ Polytriclmm, Catharinia, the opercular cap con- 

 sists of several cells (Goebel, 1. c. ). The whole mass of sperm- 

 cells is thrown out without separating the cells, and in this 

 stage the walls of the sperm-cells are still very evident. It 

 sometimes happens that the mass is thrown out before the 

 spermatozoids are complete, in which case they never escape. 

 If, however, the spermatozoids are mature, they show active 

 motion within the sperm-cells while these are still in connection, 

 and are set free by the gradual dissolution of the mucilaginous 

 walls. The free spermatozoid is much like that of Sphagnum, 

 but the body is somewhat shorter. The cilia are relatively 

 very long and thick, and as in all Bryophytes but two in num- 

 ber. A small vesicle can usually be seen attached to the pos- 

 terior end. 



Growing among the antheridia are found peculiar sterile 

 hairs, or paraphyses. These in Fiinaria are very conspicuous, 

 and consist of a row of cells tapering to the base, and very 

 much larger at the apex. The terminal cell, or sometimes two 

 or three of them, are almost globular in form and very much 

 distended. All the cells of the paraphyses contain large 

 chloroplasts, which in the globular end cells are especially con- 

 spicuous and are often elongated with pointed ends. 



The archegonia are formed while the female plant is still 

 very small, and it is much more difficult to recognise the female 

 plants than the males. The archegonia are ripe at a time when 



