CLASSIFICATION OF FERNS. 



lERNS form the Botanical order " Filices," and are divided into " Sub- 

 orders," which again are divided into "Tribes," each of which includes a 

 number of " Genera," and each " Genus " many " Varieties " or " Species." 

 I shall only notice the New Zealand ones. If you have gathered a fern 

 frondj and wish to know what it is, the first thing to be done is to look for 

 the sori ; as an examination of these will tell the sub-order, the tribe, and 

 genus to which it belongs. If it has no sori, look for a fertile frond on the 

 same plant ; or if there are none there, on a similar plant adjacent, so as 

 to get this clue. Reference to the Genus will probably show that it is divided into 

 two or more " Sub-genera;" and the sori and venation will show you to which of these 

 again it belongs. A Sub-genus also is often again divisible into classes, by some 

 peculiarity of the foliage or growth ; and thus at last you have but a very few kinds 

 from which to choose ; and the description of the plant will soon show you which of 

 these it is. Instead of a difficult task, the identification of a fern is almost as easy as 

 naming a card out of a pack. If you have any doubt, just examine several fronds at 

 different stages of growth, and your doubt will be ended : unless you have been so 

 fortunate as to find a new plant : in which case, you will be pretty sure to know that 

 too, or at all events to suspect it, and be led to compare notes with other filicists, as 

 collectors of ferns are called. The only cases likely to puzzle you are peculiar or 

 transitional forms : and these, as I have said, are rare in New Zealand. 



It may be well here to say a few words respefting the use of the terms " axillary," 

 " marginal," or " terminal " in reference to sori ; as they may give rise to the idea 

 that a sorus is a more distinct part of a frond than it really is. A fertile portion of a 

 frond is merely a changed form of a similar portion of a barren one, the sorus being 

 actually developed out of the latter, which becomes narrowed or shortened, apparently 

 to supply material for the -sorus. The terms "marginal" and "terminal" explain 

 themselves ; but " axillary " hardly does so, as it seems to indicate that the sorus is a 

 separate growth placed in the axil. This is not the case. When the term is used, 

 particularly in the case of the Hymenophylla, the sori so spoken of are aftually 



