﻿252 Transactions. — Botany. 



while in New Zealand they equal one-eighth, and the geiieral difference in 

 habit is as strongly marked. The peculiar effect produced by continuous 

 carpets of the pellucid entire fronds of Trichomanes reniforme, or the finely 

 cut Hymenophyllum demissum, in the cool open part of the forest, cannot be 

 imagined by those conversant only with the Ferns of Britain. Tree-ferns, 

 climbing ferns, and epiphytic kinds, are absent from the British Flora, and it 

 exhibits none of those handsome and delicate filmy ferns, which are so 

 luxuriantly developed in New Zealand ; still, three species, Adiantum Gainllus- 

 Veneris, Athyrium Filix-fo&mina, and Osmunda regalis, each in its respective 

 habit, surpass all New Zealand forms in grace and beauty. Fifteen genera 

 and thirteen species are common to both countries. The bracken of the 

 British Islands is represented by a closely similar plant, having as wide a 

 range of distribution, but no other Fern common to both countries has a 

 distribution in New Zealand corresponding to its range in Britain ; and the 

 same remark applies to the representative forms, with the exception, perhaps, 

 of the patotara ( Botrychium ternatuin). In conformity with the general law 

 of plant distribution, the New Zealand Ferns, and their allies, decrease in 

 number of species as they recede from the equator. In the Flora of the 

 British Islands their distribution is decidedly polar, affoi'ding a marked contrast 

 with the austral distribution of the great majority of its Phsenogams. 



Although many New Zealand Ferns occur at a great altitude, not more 

 than three or four species are so purely montane in their habit as the British 

 Woodsias, or Cystopteris montana. A few purely tropical species are found 

 luxuriating in the increased temperature afforded by the close proximity of hot 

 springs. 



Equisetum, which is a prominent genus in many parts of the British 

 Islands, has no representative in New Zealand. 



The open land in Britain is usually covered with a mixed and compact 

 growth of grasses and small forage plants, or with furze, heather, or bracken 

 interspersed with thickets of brambles, sweet-briars, dog-roses, dwarf-willows, 

 and one or two other shrubs which afford cover for a large niimber of 

 herbaceous plants and a few ferns. In New Zealand, the soiithern bracken 

 (Pteris esculenta), the manuka (^Leptos2)ermum scoparium), and, restricted to 

 the north, the tauhinu (Pomaderris ericifolia), are the chief ericetal plants 

 of social habit. These are dotted with bushes of makaka {Carmichcelia 

 australis), with its leafless branches, the z'epresentative of the yellow broom 

 of Europe, tupakihi {Coriaria ruscifolia), karamu {Goprosma lucida), koi'omiko 

 (Veronica salicjfolia, etc.), pimelias (P. prostrata, etc.), epacrids, and other 

 shrubby heath-worts, with a large number of small-growing or stunted shrubs. 

 In favourable spots a few small terrestial orchids are found of types quite 

 unknown to the British Flora. In moist places various species of Gladium 



