34 HOW TO KNOW THE MOSSES 



Carefully separate a few single plants in order to see 

 the length of the stems, the average character of the 

 leaves, and the manner of branching. It is not always 

 easy to do this without breaking the stems, especially 

 if one has no tweezers for the work. Fingers at best 

 are clumsy instruments in handling the smallest 

 mosses; possibly a wire hairpin would be of some as- 

 sistance. Sometimes two or more kinds of mosses will 

 be found growing together. If the leaves or the general 

 characters are plainly different, the student will readily 

 notice that he has collected more than one species. 

 But it sometimes happens that an apparently good 

 fruited specimen is one sterile moss growing on top of 

 another moss that is fruited, and that the fruit-stalks 

 are really attached to the moss growing underneath, 

 although they have pushed up through the conspicuous 

 growth on the surface. To avoid making a mistake in 

 such a case, always follow the fruit-stalk down to the 

 stem on which it is growing and carefully pull out as 

 long a piece of the stem as possible, and compare it 

 with the rest of the specimen. When stems with 

 numerous branches are closely interwoven, no very 

 great length can be separated and one must get the 

 average characteristics from several small pieces. 



Examine moist plants. If mosses are collected in a dry 

 condition, they must be moistened for study, as other- 

 wise leaves that can be easily seen when the plants 

 are moist may be so closely folded against the stera 

 when dry that they will not be noticed. For instance, 



