Original ^xtuh%. 



FLOWERLESS PLANTS, AND THEIR HABITATS. 



(Continued.) 



ByH. Franklin Parsons, M.D., F.G.S. 



We now come to the mosses. The word " moss " is very loosely 

 used in popular language, being applied to club mosses, liverworts, 

 lichens, algee, fungi, and even small tufted flowering plants, as 

 Sagina. The plants called mosses (Musci) by botanists form, how- 

 ever, a very distinct and easily recognisable order, and present, on a 

 miniature scale, an exquisiteness of design, an elegance of form, and 

 a beauty of colour, which, were they fifty times larger, would give 

 them a high rank among ornamental plants. The stems of mosses 

 are short, sometimes almost wanting, and rarely more than a few 

 inches in length, though in two or three of our British species they 

 sometimes exceed a foot. The leaves vary in outline, but are often 

 ovate or lanceolate, and always simple and sessile. They have usually 

 a single simple nerve, not unfrequently prolonged beyond the blade 

 of the leaf into a bristle-like point ; others are nerveless, and others 

 have two short nerves at the base. The nerve contains no vessel, but 

 consists merely of cellular tissue, as also does the stem, and indeed 

 the whole plant. The blade consists usually of bat a single layer of 

 cells. The leaves often curl up when dry, and expand when moist ; 

 and mosses are remarkable for their power of enduring drying, 

 reviving on being moistened after the lapse of years. The flowers of 

 mosses are of two kinds, sometimes found together, at other times 

 only on different plants. The male flowers consist of sausage-shaped 

 bodies called antheridia, mixed with slender threads (paraphyses), of 

 which the use is not known. The antheridia are composed of cells, 

 each containing a minute filament ; these filaments when set free 

 swim with a wriggling movement, and are the fertilizing particles. 



The Archegonia are flask-shaped bodies containing an embryo sac, 

 from which the fruit is developed. The fruit is in some kinds borne 

 at the end of the stem, in others in the axils of leaves ; the leaves 

 surrounding it are often different in shape from the others. The fruit 

 when young is covered with the calyptra, a membranous envelope 

 like that at the base of a rhubarb leaf. As the fruit-stalk elongates, 

 the calyptra is torn off at the base and carried up on the top of the 

 fruit, leaving sometimes, however, a short sheath surrounding the 

 base of the footstalk. When this night-cap is taken off the top of 



K S., Vol. iv., Oct., 1878. 



