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WHAT CONSTITUTES A FERN, 



OUBTLESS most of my readers think they can at once distinguish ferns 

 when they see them ; and yet, if a number of such plants, intermixed with 

 closely allied forms and fernlike branches, were placed before them, they 

 would make all sorts of mistakes by classing the other things as ferns, and 

 the true ferns as mosses or other growths. It is important, therefore, to 

 define a fern. To begin with, a fern is a cryptogam. Most of my readers 

 will have seen , this word, which is a Greek one signifying a concealed 

 marriage^ and, is applied to ferns, lycopods, lichens, hepaticce, &c., because 

 the manner of their reproduction was long unknown. Though they bear 

 vessels containing what was supposed to be seeds, because from them fresh 

 plants grow, yet these vessels spring direftly from the substance of the parent plant 

 without anything which, by the wildest stretch of imagination, could be regarded as a 

 blossom, to account for them. Though, therefore, these vessels were, and for conve- 

 nience still are called " fruit," it was certain that they were not true fruit, as these last 

 can only be developed from the female organs of a blossom ; and, as we have said, 

 there are no blossoms on cryptogams. It appears to be a fixed law of nature that 

 the reproduction of all organic life (except, perhaps, in some of the very lowest forms 

 in which it has not yet been detefted, though it may still be so) shall spring from 

 sexual union. The idea of what is termed Parthenogenesis, i.e., reproduction without 

 male agency in some insects, is being dispelled in the light of further scientific dis- 

 coveries. It is found that, in some cases, one male fertilisation seems to operate 

 through several generations of females, though it is now doubted whether this is really 

 so. In others, fertilisation occurs at an early stage, before the insects reach maturity 



