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HOW TO USE THE KEYS 



Suppose we have collected in late spring or eariy 

 summer a moss growing on dry soil, abundantly fruit- 

 ing and conspicuous for the dark-red fruit-stalks and 

 capsules. After soaking a piece of the specimen in 

 water for a few minutes, keeping the re- 

 maining part dry, and separating some 

 of the moistened individual plants, we 

 find they look like these. 



Let us use the Leaf Key first. We 

 find that there are two main divi- 

 sions, A and B. Under Division A we 

 read, ''Fruit at the apex of the stem or of a well- 

 developed branch, sometimes appearing lateral by 

 the new growth of the plant. Stems generally erect, 

 and often not branched; or, if slightly branched by 

 forking, usually with not more than two or three 

 branches." Under Division B we read, ''Fruit on the 

 side of the stem or on a very short lateral branch. 

 Stems prostrate or ascending, rarely erect, usually 

 much branched (with more than two or three 

 branches.)" We examine our plants and find that the 

 stems are erect with only one or two branches. The 

 fruit on one of the plants is terminal and on the other 

 two it appears lateral, but as the growth above the 

 point where the fruit-stalk is attached to the stem is 



