.2-; : HOW TO KNOW THE FERNS 



In -passing, it. may be pointed out that the term 

 Ctyptbg-a&vis a name which was originally given 

 to the flowerless plants by Linnaeus to indicate 

 that the plan of fertilization was hidden. The 

 name is still retained, but it has lost its mean- 

 ing in this sense, in that since the introduction 

 of high-power microscopes it is not necessarily 

 more difficult to study the fertilization of the 

 non-flowering plants than it is to watch the 

 process in the kinds which bear blossoms. 



A small acquaintance with the Vascular 

 Cryptogams will show us that they approach 

 very closely to the flowering plants, or Phanero- 

 gams, as they are called, in their general features. 

 It is true that in the cases of the Club Mosses 

 and Horsetails the leaves are small or very 

 poorly developed, but with the Ferns the foliage 

 is often of an advanced type. All the Vascular 

 Cryptogams, apart from a few insignificant ex- 

 ceptions, produce real roots ; and. as the name 

 implies, in a botanical sense, evidence woody 

 tissue in their composition. Whilst the Club 

 Mosses and Horsetails are comparatively humble 

 plants, the Ferns have reached a remarkable 

 development in the arboreal species. These, of 

 course, grow into large trees which may be fifty 

 or more feet in height, with thick woody trunks. 

 Our common Male Fern not infrequently forms 

 a short trunk-like stem if it is allowed to remain 

 in an undisturbed state for a number of years. 

 Not all the Ferns are large or even of moderate 

 size ; many of the Filmy Ferns are so minute 

 that they are often taken for Mosses by those 

 who do not know any better. 



All the Vascular Cryptogams show an alterna- 

 tion of generation ; that is, in the life history of 

 each plant there is a sexual and an asexual 

 individual. As is fully explained later, the 



