164 CRYPTOGAMOUS OR FLOWERLESS PLANTS. [SECTION 17. 



end of the stem. The analogue of the anther (Antheridium) is a cellular 

 sac, which in bursting discharges innumerable delicate cells floating in a 

 mucilaginous liquid; each of these bursts and sets free a vibratile self- 

 681 68* 611 540 



moving thread. These threads, one or more, reach the orifice of the pistil, 

 shaped body, the Pistillidium, and act upon a particular cell at its base 

 within. This cell in its growth develops into the spore-case and its stalk 

 (when there is any), carrying on its summit the wall of the pistillidium, 

 which becomes the calyptra. 



501. Liverworts or Hepatio Mosses (ffepaHece) in some kinds re- 

 semble true Mosses, having distinct stem and leaves, although their leaves 

 occasionally run together ; while in others there is no distinction of stem 

 and leaf, but the whole plant is a leaf-like body, which produces rootlets on 

 the lower face and its fructification on the upper. Those of the moss-like 

 kind (sometimes called Scale-Mosses) have their tender spore-cases splitting 

 into four valves ; and with their spores are intermixed some slender spiral 



FIG. 529. Mnium cuspidatum, smaller than nature. 530. Its calyptra, detached, 

 enlarged. 531. Its spore-case, with top of stalk, magnified, the lid (532) heing 

 detached, the outer peristome appears. 533. Part of a cellular ring (annulus) 

 which was under the lid, outside of the peristome, more magnified. 534. Some 

 of the outer and of the inner peristome (consisting of jointed teeth) much magni- 

 fied. 535. Antheridia and a pistillidium (the so-called flower) at end of a stem 

 of same plant, the leaves torn away ( g, antheridia, 9, pistillidium), magnified. 

 536. A bursting antheridium, and some of the accompanying jointed threads, 

 highly magnified. 537. Summit of an open spore-case of a Moss, which has 

 a peristome of 16 pairs of teeth. 538. The double peristome of a Hypnum. 

 639-541. Spore-case, detached calyptra, and top of more enlarged spore-case 

 and detached lid, of Physcomitrium pyriforme (Fig. 527) : orifice shows that there 

 is no peristome. 



