Growth-Forms, 117 
germination of many young trees and shrubs and for the ramification of the 
slender wiry stems of the Aymenophyllaceae, some being confined thereto, 
others commoner there than elsewhere and others again equally at home on 
the forest-floor. “The occurrence of many of the spermophytic epiphytes and 
the larger pteridophytes is bound up with the prior occupation of trunks an 
branches by epiphytic bryophytes which, in their turn, occupy their epiphytic 
station thanks to the water-absorbing capacity of their leaves, the sponge-like 
cushions, mats or masses they build so rapidiy and various special water-holding 
contrivances. Soon sufficient soil is formed from the decay of the ee 
to support seedling epiphytes and these, each according to its specific ca 
bility, make more soil from its decaying leaves &c. until a surprising ae 
of vegetable matter in various stages of decay accumulates on horizontal boughs 
and forks of branches amply sufficient to support shrubs and herbs of no 
mean size. 
The epiphytic species of Astelia are of great physiognomic importance 
5 and also of peculiar interest, since they are ecologically equivalent to the tro- 
pical epiphytic Bromeliaceae and like them store up water. A. Solandri is a 
densely tufted evergreen herb with numerous, ensiform, coriaceous leaves 
90 cm—ı.2 m long with black, sheathing, fleshy bases covered with a great 
quantity of long silky hairs. These leaf-sheaths, even in quite dry weather, 
hold large quantities of water. The plant forms immense tufted masses high 
up on the tree-tops, the basal part and earlier leaves decayed and making a 
usually sopping-wet mass of loose vegetable matter. The plant frequentiy 
grows on slender perpendicular trunks in what appears an impossible position 
for a plant so massive and heavy (Plate XXI, Fig. 27). 
Pittosporum Kirkii and P. cornifolium are sparsely-branched - straggling ie 
shrubs with long, flexible branchlets, those of the latter being slender and droop- 
ing. The leaves of both are coriaceous but those of P. BRFARRE 
Griselinia lucida is, at times, almost a bushy-tree w 
The leaves. are bite oa thick, oriaceı 
—_ 
bark. 
very small. % small 9; medium 9; 1 arg 
thin 15; very thick or er Fer 
degree 5: grass-like 3. A few 
