PARTS OF FERNS. 13 



roots, and was formerly eaten by the Maoris ; and in two others (Adiantum diapha- 

 num and Nephrolepis cordifolia) the true roots produce little tubers full of starch, 

 which would no doubt make good food if only they could be gathered in sufficient 

 quantities, as the tubers of the latter are said to be in the Pacific islands. In some 

 ferns these tubers will produce plants. The rhizome of Lygodium articulatum climbs 

 along, sometimes for hundreds of feet, and ascends to the tops of the highest forest 

 trees, hanging in graceful festoons from bough to bough ; and is so hard and tough 

 that the Maoris made it into fish-hooks, and used it for ropes : while the Alsophila 

 Colensoi has what can only be called a decumbent caudex. One tribe of ferns, the 

 Ophioglossaceae, can hardly be said to have rhizomes, as the fleshy roots branch out 

 immediately below the surface of the ground. An English fern, " Lastrea cristata," 

 though it appears to have an erect rhizome, continually shifts its position. Take what 

 pains one will to put it exactly in the centre of a pot, in a few months it will travel to 

 the side ; and if left alone will burst the pot in its efforts to escape. The real fact is 

 that the rhizome is actually a slowly creeping one, but the fronds grow erect from its 

 end, and so it looks as if the rhizome were erect. It will be worth while to note 

 whether any of our N. Z. ferns have the same habit ; Asplenium umbrosum, particularly 

 a Wanganui form of it, appears to have it. From the above it will be seen that there 

 is much to interest an observer even in so humble and often inconspicuous a portion 

 of a fern as the rhizome and roots. 



The principal or leafy portion of a fern consists of " fronds," leafy branches so 

 called because they partake of the characters of both branch and leaf. They vary 

 greatly in size, those of the largest tree ferns and some others attaining the length of 

 from ten feet to twenty feet ; while those of Hymenophyllum Cheesemannii and Tri- 

 chomanes Armstrongii seldom, if ever, exceed half an inch. Ferns are classed ac- 

 cording to the character of their fronds ; the position and nature of their fructification 

 determining their tribe and genus, and the other peculiarities the sub-genus and 

 species ; the specific name often describing some main peculiarity, though in many 

 cases it is that of the discoverer of the plant or given in compliment to some one. 



The stem of a frond which connects it with the rhizome or caudex, and resembles 

 the stalk of a leaf, is called the " stipes" (sti-pes : plural, sti-pit-es). It varies greatly 

 in colour and other particulars in different ferns, and often has a groove or channel 

 along the whole or part of its upper surface. The continuation of it to the top end of 

 the frond is called the " rachis" (ra-kis) and sometimes the " mid-rib." This latter 

 term is also applied to the central stems of the lateral branches of fronds, but the 

 correct botanical name for such a stem is a " costa" (plural, costae). The term frond, 

 therefore, though often used to express all above the rhizome, applies, strictly speak- 

 ing, only to the leafy portion. When a frond consists merely of one even-shaped leaf, 

 as it were, it is called " simple," " entire," or undivided" ; though its edges may be 



