36 HOW TO KNOW THE MOSSES 



To see the shape of the leaves or the color of the stem, 

 hold the plants to the Hght or in strong light, or against 

 something white. The leaves that are best developed 

 are usually along the middle part of the stem. If the 

 leaves conceal the stem too much, strip them off by 

 drawing the stem from the tip toward the base through 

 the firmly pressed tips of thumb and finger. Red stems 

 usually show through the leaves. 



Do not mistake branches for leaves. As the leaves of 

 mosses are so much smaller than those of other plants 

 and the branches are often more conspicuous than the 

 leaves, care must be taken to avoid this mistake. 

 When the plants are held to the light, in most cases 

 the leaves, or at least the leaf -tips, can be seen stick- 

 ing out around the stem and the branches. If the 

 leaves are too small to be seen, the cylindrical appear- 

 ance of the branches and their arrangement on the 

 stem should be sufficient to distinguish them from 

 leaves. (See Plates II, III.) 



// in doubt about the length of the stem or the shape of 

 the leaves, try the moss under each head. The length 

 of the longest stems is given and the characteristics of 

 the largest leaves. To see these, examine several indi- 

 vidual plants. 



When estimating the length of the stem, do not include 

 the fruit-stalk. The length that is given is measured 

 from the rootlets only through the leafy portion and 

 does not include the seta. (See ''Illustrations of 

 Terms," Plate I, Fig. i.) 



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