49 



same length of time is required by Philonotis, and by some 

 species of Br yum and some of Polytrickum, which blossom 

 in May and June."* 



The capsule is usually borne on a long slender footstalk, 

 but in some species this is partially or entirely suppressed, the 

 capsule peeping out from the enfolding leaves, as in Dalto?iia, 

 Cinclidotus, Diphyscium, Fontinalis. Some species of Grim- 

 mia, when the capsule is full grown, hide it among the 

 foliage. Though the general form of the capsule is more or 

 less ovate, in Bartramia and Phascum it is spherical, in 

 Tortula it is narrower, and of greater length ; in Polytri- 

 ckum, as we have seen, it is quadrangular, and in Funaria 

 pear-shaped. The teeth of the peristome are always some 

 multiple of 4 — 8, 16, 32, or 64 — usually 16 or 32 in number. 



Then, too, we should not omit to observe that the method 

 by which the capsule opens is not in all species the same as 

 we have described in Polytrichum. Sphagnum, for instance, 

 opens by simply casting off the operculum ; there is no peris- 

 tome. The species of split mosses {Andrecsa) have a lid to 

 the capsule which does not separate from it ; instead, the 

 capsule opens by means of four slits in its walls, which ex- 

 tend almost to the base and the summit. In dry weather 

 these slits open wide, and in damp weather close up. There 

 is no peristome here. In the earth mosses (Pliascum), again, 

 there is no peristome ; and the capsule does not open, the 

 spores being liberated only by the decay of that organ. 



There is also great variety in the size of the spores. 

 According to Schimper, the spore of Archidium is \ th of a 

 millimetre in size, and only sixteen spores are found in each 

 capsule ; whereas in Dawsonia the measurement of each spore 

 is scarcely ^oth of a millimetre. As a rule, the smaller the 

 species of moss, the larger are the spores produced by it. 

 Some of these spores, when sown under favourable conditions 

 as regards the dampness of the soil, germinate in two or three 

 days, and produce, first, the green felt-work, from which in 

 about three weeks the true stem, clothed with leaves, begins 

 to arise. This is true of Funaria, Gymnostomum etc. ; whilst 



* Klinggraff, quoted by Sachs. 

 E 



