THE FERN BULLETIN 



49 



forms that are often many times compound. So, too, 

 in the matter of size, there are species, small and in- 

 conspicuous, almost lost among the other herbage of 

 their haunts and others that reach sizes that render it 

 impossible for them to escape notice. After one has 

 spent a day collecting polypodies so small that it is nec- 

 essary to carefully examine the mossy tree-trunks up- 

 on which they grow in order to rind them at all, it is 

 an impressive contrast to find on the way home some 

 species such as Polypodium crassifolium with fronds 

 like broad-swords. 



Nor do size and delicate cutting have any necessary 

 relationship. The large fronds are as likely to be 

 deeply cut as are those of small species but no more so. 

 In the case I have mentioned both forms happen to 

 have entire fronds, though one is possibly fifty times 

 larger than the other. Size very frequently depends 

 upon habitat. In ground inhabiting species, there is 

 usually no reason for a diminution in size, but those 

 species which live upon trees, must keep their propor- 

 tions within the bounds which their habitat places upon 

 moisture, light and root-hold. 



Some thoughts of this nature must pass through the 

 mind of anyone who examines any extended series of 

 tropical Aspleniums. At one end of the list is the great 

 simply pinnate fronds of Asplenium marginatum like 

 a gigantic Asplenium angustifolium, taller than a man 

 and at the other is the little Asplenium pumilum chosen 

 to illustrate this article. Although so small our fern 

 does not grow on trees or rocks, but is to be found 

 among the grasses and herbs on shrubby half open 

 hillsides. The variation in the fronds presented by the 

 fertile, and therefore presumably mature, plants would 

 delight those botanists who thrive by making distinc- 



