214 HISTORY OF BRITISH FERNS. 



phosed terminal bud of a main axis, and the smaller 

 granules, as lateral buds, or twig buds, only to be distin- 

 guished from the terminal bud which is developed into the 

 oophoridium, by the circumstance that the latter is a prin- 

 cipal branch, possibly capable of a more extensive develop- 

 ment into branch and foliaceous organs ; while the twig, 

 which is developed into an antheridium, is but a small 

 particle of such a main branch. 



These plants, like the Ferns, are most abundant in hot, 

 humid, and especially insular situations in the tropics, 

 becoming scarcer northwards, but often, even in very 

 northerly regions, covering large tracts of land. Our native 

 species, with one exception, have a boreal and alpine ten- 

 dency ; being found most abundantly on the high lands of 

 the north, and decreasing in quantity as they advance 

 southwards. Many of the tropical Lycopod'mms are ex- 

 tremely beautiful : some are of scan dent habit, and many 

 of them attain considerable size. 



Though of humble growth, and altogether unattractive 

 in appearance, the Club-mosses are not without their use. 

 More than one species is used in dyeing operations, and 

 several have a medicinal reputation. The powdery spores, 

 often called pollen, produced in considerable quantities by 



