HELPFUL SUGGESTIONS 35 



the leaves of Pogonatum hrevicaide (p. i6i) are long and 

 narrow, easily seen when moist, though few in num?jer, 

 but when dry they fold against the stem and one is 

 liable to overlook them and misplace the moss under 

 *' Leaves when moist not easily seen." Mosses may 

 remain dry for an indefinite period and then can be 

 restored to fresh conditions by being placed in water. 

 Quickest results can be obtained by using hot water. 

 This process of reviving dried mosses may be repeated 

 as often as required, without injury to the plants. 

 When the leaves have fully expanded, remove the 

 plants from the water and absorb the extra moisture 

 with soft linen. The leaves of a few species dry so 

 quickly that it may be necessary to replace the plants 

 in water two or three times while studying them. If 

 plants are allowed to remain in water for a number of 

 days, the leaves and capsules lose their natural color 

 and turn dark. 



To dry mosses, separate the individual plants and 

 place them in sunKght or merely expose them to dry 

 air. In case they do not dry readily, a Httle artificial 

 heat may be used by taking the plants in a pair of 

 tweezers or between the ends of a wire hairpin, or by 

 placing them on a piece of paper and holding tliem 

 near a light or over some source of heat; but if too 

 much artificial heat is used, making the leaves dry too 

 quickly, they do not come into the characteristic dried 

 condition. Pressure should not be used for naturally 

 dried plants. 



