FERN ALLIES OF NEW ZEALAND. ( 



ought to be that where the blade is distinctly interrupted into 

 separate pinnae or portions, the term pinnate, or 2- or 3-pinnate, 

 should be employed; but if the portions are united by continuations 

 of the lamina, the frond is still a simple one, and the term pin- 

 natifid should be adopted. It will still be found, however, that the 

 application of the rule is by no means easy, as many ferns are 

 pinnate below and pinnatifid above, and nothing but practice and 

 good observation will enable anyone to apply the correct terms. 



The venation of our Asplenium is seen to be different from that 

 of both the others examined, the midrib which traverses each p inn ule 

 sending out single unbranched veins alternately to each of the lobes 

 or to their ultimate segments. Along one side of each of these veins, 

 and placed obliquely to the midrib, is attached a slender, elongated, 

 pale-coloured membrane — the involucre— caverm-g the linear sorus. 

 When the spores are mature, this ruptures along the side next the 

 margin of its segment, and discloses to view the sorus formed of a 

 dense line of closely-crowded capsules. Near the extremity of many 

 of the segments of this fern small swellings or outgrowths, bearing 

 a few very young leaves, may be noticed. These are the bulbils or 

 gemmce, from the presence of which the species received its second 

 name — bulbiferum, or bulb-bearing. Plants bearing such bulbUs 

 are said to be proliferous. If these little growths, together with a 

 small portion of the frond to which they are attached, be removed 

 and planted in fine, damp soil, they wiU grow into new plants. 



If we now seek to apply all the terms we have learned to other 

 ferns, we shall find that the same organs show many diversities of 

 structure besides those afibrded by our three selected examples. We 

 shall consider the parts in the order already followed. 



The rhizome in many species is very much elongated, creeping 

 underground in some, as in the common Bracken (Fter.is aquilina), 

 or above-ground, as in one of our commonest Maidenhairs {Adiantum 

 affme). In tree-ferns it is eloligated into a more or less erect trwnh 

 or cavdex, the upper part of which is often clothed with the bases of 

 the stipes of old and withered fronds, while the lower portion is 

 usually thickened by root-fibres. Between the long creeping or 

 climbing rhizome of some species, and the stately trunks — often 20 

 to 40 feet high — of some of our handsomest tree-ferns, a nearly 

 continuous gradation may be noticed. 



