4 MK. J. BUCHANAN ON THE 



the frond has performed its functions. The articulated surface 

 of the scale shows a scar-mark much resembling the imprint of a 

 horse-hoof. It is probable that the mobility of the stipe men- 

 tioned by Colenso takes place immediately before separation, 

 after decay at the articulation has commenced ; but I have not 

 observed this. 



Such a rootstock approaches the scaly bulb more in structure 

 than a fem-rhizome, but v^ithout a central mass round which the 

 scales might be arranged in order. 



The continued addition of new scales outwards and upwards 

 often raises the rhizome above the surface of the ground ; but 

 the frond-buds of those scales only which are in contact with the 

 soil throw out independent roots. This form of rootstock may 

 therefore be named a scaly subaerial rhizome without internodes. 



The procedure in propagating Marattia by scales is very similar 

 to that of the common potato. When the plant is grown from a 

 detached scale, the buds may sprout from any part of its surface, 

 differing in this respect from the potato in having neither points 

 nor eyes; and when a frond-bud springs from the crown of the 

 rhizome or from a scale above the surface of the ground, it derives 

 its nourishment through the parent scales. The bud swells to a 

 considerable size before the crozier bursts through the cuticular 

 bark ; during this process the latter is split and the edges car- 

 ried upwards, forming the so-called adnate stipules of authors, 

 and remains as a sharp ridge round the scar where the stipe arti- 

 culated. The new stipe begins to swell at its base at a very early 

 period, spreading over the adjacent surface and forming a new 

 scale. 



The growth of the Marattia rhizome is remarkably slow, being, 

 under favourable circumstances, only one inch diameter in one 

 year ; and as the height is less than the diameter, it may be safely 

 calculated that a Maori will consume in one day the growth of five 

 years, which fact may account for this fern becoming rare in cer- 

 tain localities. The rhizome, by a process of renewal and move- 

 ment, lives for an indefinite time, shifting its position in the 

 ground by its growth outwards from a centre, the exhausted scales 

 a<jcumulating in a hard mass on the original site. In this way, 

 as in certain fungi, rings or detached clumps may be formed at 

 equal distances from the centre if no obstruction exists. 



Before the exhaustion of any part of the rhizome mass, adven- 

 titious frond-buds may sprout from any part of its surface either 

 above or below ground. 



