340 



THE MICROSCOPE AND ITS REVELATIONS. 



336. What has commonly been regarded as the- ' fructification ' of 

 Mosses namely, the i urn ' or ' capsule ' filled with sporules, which is 

 borne at the top of a long footstalk that springs from the centre of a 

 cluster of leaves (Fig. 219, A) is not the real fructification, but its pro- 

 duct; for Mosses, like Liverworts, possess both antheridia and arcliegonia, 

 although they are by no means conspicuous. These organs are some- 

 times found in the same envelope (or perigone), sometimes on different 

 parts of the same plant, sometimes only on different individuals; but in 



TIG* 220. 



\ntheridia and Antherozoids of Polytrichum commune: A, group of an thendia, mingled with 

 hairs and sterile filaments (paraphyses> : of the three antheridia, the central one is in the act of 

 discharging its contents; that on the left is not yet mature ; while that on the right has already 

 emptied itself so that the cellular structure of its walls becomes apparent; B, cellular contents 

 of an antheridium, previously to the development of the antherozoids; c, the same, showing the 

 first appearance of the antherozoids; D, the same, mature and discharging the antherozoids. 



either case they are usually situated close to the axis, among the bases of 

 the leaves. The ' antheridia' are globular, oval, or elongated bodies 

 (Fig. 220, A), composed of aggregations of cells, of which the exterior 

 form a sort of capsule, whilst the interior are sperm-cells,' each of which, 

 as it comes to maturity, develops within itself an ' antherozoid ' (B, c, 

 D); and the antherozoids, set free by the rupture of the cells within which 



