142 The Plant World. 



All of them are shallow rooted and some of them have very pe- 

 culiar root systems. Weinmannia racemosa, for instance, begins 

 life as a seedling on a fallen log, or a tree fern trunk, and as it 

 grows sends branch-like roots to the ground, so that eventually 

 the trunk, or trunks, for there are usually more than one, arise 

 from the summit of an entangled mass of large roots. 



Curiously enough the leaf epidermis of this tree has a dis- 

 tinctly xerophytic structure, hardly to be expected in a native of 

 so moist a climate. But, in point of fact, there are among the 

 plants of the islands those which possess the specialized anatomi- 

 cal structure, or such protective adaptations as a hardened or 

 a reduced leaf surface, a tomentum or a varnish, which we are 

 accustomed to associate with excessive aridity and insolation. 

 Here they may rather be considered defenses against the evapor- 

 ating effect of the winds. 



The same force,- the wind, exerts a great modifying effect 

 on the form and even on the vegetative character of some of the 

 plants. Thus, Lepiospermum scoparium, in sheltered situations, 

 is an erect tree twenty feet high ; exposed, it becomes absolutely 

 prostrate, and forms a dense fan-shaped mat. The small ultimate 

 branchlets, not over an inch and a quarter long, rise erect, and 

 are so compacted as to present the appearance of a sward. 

 They put down roots into the soil, and eventually the main trunk 

 becomes entirely functionless. Drachophyllum politum has such 

 a turf-like form, but it may also be a trailing shrub, with virgate 

 stems eight or nine feet long; or it may be a dense, compact 

 cushion, two or three feet in diameter. 



Cushion plants are, indeed, a notable feature of the island 

 flora. They are formed by densely tufted branches dividing 

 into very short branchlets, whose extremities are covered with 

 closely imbricated small leaves, all pressed together into a com- 

 pact, hard mass. Such a plant is Rasulia Goyeni, which "looks 

 more like a lump of coral than a living plant." 



Another form of cushion plant is presented by some species 

 of mosses and liverworts. These have the appearance of large 

 moss-covered boulders, but are, in reality, water-logged masses 

 of dead stems and roots, the extremities only being alive. 



Sometimes the forest floor is carpeted with other Bryophytes 

 abundantly intermingled with delicate ferns. The numerous 

 species and the indescribable profusion of these Archegoniates 



