THE "CLUB-MOSS." 



Selaginella sp. 



PTERIDOPHYTES; LYCOPODIALES J SELAGINELLACE^E. 



PRELIMINARY. 



IN the Lycopodiales, the order to which this plant 

 belongs, there are only a few genera. These bear much 

 general resemblance to one another, although they are 

 quite unlike in several important details. Selaginella 

 is one of the few living plants that are intermediate in 

 certain characters between other Pteridophytes and the 

 lowest Spermatophytes. Most of its species are found 

 in the warmer temperate regions and the tropics, although 

 a few inhabit the colder temperate regions. Some spe- 

 cies are commonly grown in greenhouses, where the fruit- 

 ing spikes may often be found and collected for class use. 

 Fresh material will be much better for study, but the plant 

 retains its characters in alcohol and formalin, and may 

 thus be kept indefinitely for class use. If S. rupestris 

 can be obtained it will be found highly satisfactory. 



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