SECT. vii. MUSCL 323 



SECTION VII. 



MTJSCI, OR MOSSES. 



MOSSES approach the higher classes of vegetable life 

 in having roots, and a more or less upright stem or axis 

 of growth. Like all other plants, they are chiefly formed 

 of cellular tissue, yet, in the stems, there is an indication 

 of a separation between the bark and pith by the inter- 

 vention of a circle of elongated cells approaching to 

 woody fibre, which passing into the branches and leaves 

 form a kind of midrib, either extending to the extremity 

 of the leaf or not. The delicate little leaves, which are 

 arranged with great regularity, consist of a single or 

 double layer of cells united by their flattened sides, and 

 rarely exhibiting any epiderm or skin. Green is the 

 prevailing colour in this order of beautiful little plants, 

 but, when exposed to the sun and much moisture, they 

 sometimes become red. 



The urn-like vessels (fig. 47 B), containing the spores, 

 are either terminal or lateral on the stem of the moss, 

 and rise on a slender stalk from a rosette of narrow leaves 

 possessing a skin perforated by stomata or breathing 

 pores of simple structure. This is the ultimate result 

 of fructification; for at a very early period, while the 

 rosettes of narrow leaves are merely buds, they contain 

 antheridia and archegonia, the latter or female organs 

 being either inclosed in the same bud, or in different buds 

 placed on the same or on different plants; but how- 

 ever that may be, the buds are invariably placed at the 

 base of the leaves, close to the axis of the plant. 



T 2 



