THE BRYOPHYTES 



275 



(J) The blade, of thin-walled 

 cells containing many chlorophyll 

 grains. 



(c) The border, of strengthening 

 cells, some projecting into teeth. 

 Draw. 



353. Minute Structure of the Gam- 

 etophyte, Reproductive Portion. — 

 Dissect with needles, in water, on 

 a slide, the tufts of leaves found at 

 the tips of some sterns.^ Note : 



(a) The antheridia, oval sacs grow- 

 ing from the enlarged tips; tips of 

 the stem (see Fig. 201 for a single 

 one much magnified). 



(b) The arcliegonia, fiask-shaped 

 structures arising from the tip of the 

 the stem (Fig. 202). 



(c) The sterile filaments inter- 

 mixed with the sex organs (Fig. 

 202.) Are the antheridia and arche- 

 gonia of Mnium cuspidatum borne in 

 the same leaf tuft or separately? 

 Draw (a), (V), and (c) in position. 



366. Minute Structure of the Spo- 

 rophyte. — Procui-e plants showing 

 sporophytes in various stages of de- 

 velopment. Draw a series of these, 

 attached to the tips of the leafy stems 

 from which they grow. Boil some 

 stems with attached sporophytes in 

 five-per-cent jfctash solution for a 

 few minutes, rinse with water, care- 

 fully pull out the sporophyte from 

 the tip of the gametophyte, and 



1 It will be of decided advantage also 

 to study prepared microtome slides of 

 longitudinal sections of these tufts. 



EiG. 200. Development of Sporo- 

 phyte of a Moss (Funaria). 



A, a very early stage, showing the 

 cell-divisions of the egg; JB, the 

 sporophyte lengthening rapidly 

 and about to tear off the arche- 

 gonium, which will be carried up 

 as the hood of the spore-capsule. 

 The base of the sporophyte is fas- 

 tened to the tissues of the game- 

 tophyte (leafy moss-plant), into 

 which it is inserted for a consid- 

 erable distance ; a, archegonium ; 

 g, gametophyte ; s, sporophyte. 



