INTRODUCTION. 9 



Tlic germination of the spore in mosses pro- 

 duces at first a thread-like protonema, which 

 might be mistaken for a conferva, upon wliich butls 

 are developed, and these are the rudimentary moss- 

 plants. In the Hepatics there is commonly a less 

 distinct protonema. In frondose or thalloidy?/;/- 

 gcr))ian)iiac€ie a lamina is formed, from which the 

 frond is produced, or, in some of the foliaceous 

 species, a ribbon of cells passes into a stem and 

 leaves ; or, in other cases, the stem bud proceeds 

 direct from the spore, whilst in some cases there is a 

 proper protonema. In Radula for instance there is 

 a well-defined body of a cake shape, which sends 

 out rootlets from beneath, and ultimate!}-, fiv^e 

 months after sowing, a bud at the margin indicates 

 the commencement of growth of a young plant. 

 This developes gradualh' b}- apical growth into 

 stem and bilateral leaves. 



The modification which the leaves undergo as 

 they approach the reproductive organs, and be- 

 come converted into bracts, may be alluded to 

 further on. 



There are two methods by which the species may 

 be perpetuated, independently of ordinarj- fructifi- 

 cation. This is accomplished, as the stem dies olt 

 behind, by the branches becoming disconnected 

 and independent, and, in the frondose species, by 

 adventitious frondlets becoming similarly detached 

 and forming new plants. The other method is by 

 gemmation. Cells will sometimes detach them- 

 selves from the margin of leaves, as gemma;, or 

 buds, and grow independently. In other cases the 



