A MOSS 



91 



attached to the spore sac, is somewhat enlarged ; many of 

 the cells of this part contain chlorophyl, and so -can make 

 carbohydrate food. 



The spore sac (Fig. 46, B) has a rather complex structure, but the 

 important thing for us to note is that the spore-bearing part is in the 

 form of a hollow cylinder, and that inside and outside this spore-bear- 



FlG. 46. — A, the upper end of the spore-bearing (asexual) plant of 

 Funaria, stiU carrying the cap (r) which was formed from the archegone. 

 B, a spore sac (as seen in lengthwise section) from which the cap has fallen; 

 I, the part of the sac which will form the Md; sp, spore-bearing region; 

 st, enlarged upper end of the stalk. C, two teeth from the upper end of the 

 spore sac. B after Sachs. 



ing region are various layers and groups of cells which make and store 

 food, and which have nothing directly to do with spore formation. 

 Many of these food-making cells, like those in the upper enlarged part 

 of the stalk, contain chlorophyl. Since so many cells in the spore sac 

 and in the stalk can manufacture food, this spore-bearing plant is not 

 wholly dependent upon the parent plant to which it is attached. How- 

 ever, since it is not directly coimected with the soil, the spore-bearing 

 plant must take from the parent its whole supply of water and of the 

 other food substances that come from the soil ; to this extent, there- 

 fore, it is parasitic upon the parent plant. The spore sac is curved ; 

 the upper part of the stalk also bends as the sac becomes mature, so 



