166 ME. T. S. EALPH ON THE 



seems to recover strength and determination to ascend more 

 straightly than before. 



It is to be observed that as the stem attains a height of ten feet, 

 or thereabouts, the stipites become shorter, or, in other words, the 

 pinnae are set closer to the base of the stipites — but these last still 

 continue close-pressed to the stem, — that the black colour above is 

 replaced by a yellowish green, and greater asperities make their 

 appearance beneath, and are extended now all the way up the 

 rachis. The rachis in its outline is altered from the rounded to a 

 flattened form ; and as it springs from the stem, it assumes a gentle 

 curve, so as to bring the frond to a horizontal position. The fronds 

 are now seldom more than twelve feet in length, and of such a 

 weight as to require considerable efibrt to raise them off the ground 

 by one end in order to shoulder them, when one may be readily 

 carried. At this more mature stage of growth, the fronds, when 

 fully ripened, decay somewhere about six inches from their inser- 

 tion into the stem, and no doubt suddenly fall from their hori- 

 zontal position to a pendent one, and remain suspended perhaps 

 during the greater part of the winter, giving a majestic tree fern 

 the appearance of wearing a clothing of matting, much like a 

 native chief. These fronds ultimately fall off, and leave the stem 

 almost bare, so as to show the scars. This fern is seldom beset 

 by climbing plants, — a circumstance possibly due to the long per- 

 sistence of the stipital remains. 



If the stem of 0. meduUaris, of a height varying from 20 to 40 

 feet, be examined, the following will be the features it will present. 

 A large, rough, black, triangular-shaped buttress tapering upwards 

 to 6 or 8 feet, when the original stem will most likely be seen 

 marked with elliptical-shaped scars of 6 or 8 inches in length 

 and about 3 in width. As the eye is carried higher up, these scars 

 will be seen to be set closer together, and to become altered in 

 form ; and at a height of 20 feet and upwards, they become nearly 

 hexagonal, and very regularly placed ; so that six of them occupy 

 the circumference, while the six above and those below alternate 

 with them. The woody matter at this part is very hard and heavy 

 with sap. 



I have counted about 34 or 36 fronds in full vigour in one 

 crown at one time ; and, supposing that a circle of fronds attain 

 their full growth and live only six months, it will be seen that 

 these ferns are slow growers. 



The linear form of the scars below accords with the brittle 

 nature of the rachis and their mode of intortion, by which a great 



