«3 



means adaptability, was that sooner or later all the varying 

 conditions of the earth's surface, drier or wetter, warmer 

 or cooler, sunnier or shadier, eventually found occupants 

 to lit them. Presumably for a long period dense cloudy 

 skies, frequent torrential rain, and fierce and stormy winds 

 prevailed, under which these lowly growths alone could 

 flourish and maintain their footing. But presently the 

 skies cleared, and under the vitalising sunbeams, an 

 elevating impulse lifted the creeping moss into the huge 

 tree-like lepidodendron ; the Calamites, now our equisetum, 

 aped the fir tree, and last, but not least, in some occult 

 fashion the fern frond was evolved as the fruit-bearer of 

 some lowlier type of Marchantiform vegetation, and was 

 differentiated into many genera and species prior to its 

 final evolution, in conjunction with its allies, through some 

 of their members, into trees, shrubs, and flowering plants 

 which now adorn our globe. 



In the maidenhair tree (Salisburia adiantifolia) we have a 

 still existing link 'twixt fern and forest tree, and in many 

 of our conifers we may still detect the structural features 

 of the lycopods of long ago. It is a peculiar fact that this 

 adherence to ancient types is coupled still with an inde- 

 pendence of that insect aid to reproduction which has 

 metamorphosed our flowers, the pollen of most if not all 

 conifers being windborne, thus excluding one potent factor 

 of change. It is a curious fact, too, that despite the 

 enormous lapse of time since their first evolution, and 

 since the coal age in which we find them so grandly 

 developed, the method of reproduction has been so rigidly 

 adhered to that to this day we find the first phase of fern 

 life engendered by the spore, to be to all intents and 

 purposes, lichen-like; a small green scale attached to the 

 soil by root-hairs, and sometimes proliferous, so that a 

 single spore may not only cover a relatively considerable 

 area of soil with a marchantoid growth, but this may exist 



