BEITISH MOSSES. 9 



Now I will ask the reader to look at the column under 

 the word " Series." The Pleurocarpse or Pleurocarpous 

 Mosses are those which carry their capsules on stalks pro- 

 ceeding from the sides of the axis of growth ; the 

 Acrocarpse or Acrocarpous Mosses are those which bear 

 these capsules on the top of their axis of growth. This 

 distinction will be readily understood by comparing Fig. 1, 

 which is a Pleurocarpous Moss, with Figs. 2 and 3, which 

 represent an Acrocarpous Moss ; in the former it will be 

 seen that the axis, or line of growth, is horizontal, that 

 $& a the plant, in short, grows along the 



ground, whilst in the latter the 

 direction of growth is vertical. 



Again, in the former the capsules 

 c c are seen carried on stalks origin- 

 ating from the principal stem, whilst 

 in Fig. 2 the capsule a crowns the 

 line of growth. This distinction in 

 the mode of carrying the capsule is 

 one of great importance in the classifi- 

 cation of Mosses, and the student who 

 desires to begin to learn them should 

 pay early attention to it. Often it 



FIG. 3. Polytrichum: j s perfectly easy of application, but 

 Male Plant. After . 

 Dillenius. a. Male intermediate forms occur which are 



Blossom. puzzles, and go to show that the 



chasm between the two forms is bridged over in Nature. 



Life-History, I propose now to trace the life-history of 

 a Moss in its most complete course of life, and I shall then 

 show how, in many cases, this course is abbreviated. It 



