420 ZONES AXD REGIONS [Pt. Ill, Sect. II 



becomes cooler, and together with mosses play the chief part as epiphytes 

 and lithophytes in forests, particularly of the cold temperate belt, as well 

 as on rocks and stones. It has been already stated ' that, in the temperate 

 zones, Fniigi exhibit many more large forms belonging to the Ascomy- 

 cetes and Basidiomycetes than in the tropics, and they are therefore more 

 conspicuous, in spite of apparently weaker development. 



Bryophyta. 



Bryophyta, in particular Mksci, constitute in the temperate zones much 

 more essential constituents of the vegetation than in tropical lowlands. 

 In particular, moist cool districts with a maritime climate, for instance 

 Western New Zealand, the Atlantic coasts of Europe, the North Pacific 

 coasts of America, Tierra del Fuego, are very rich in mosses. 



Pteridophyta. 



Filicincac are dependent on conditions of existence similar to those of 

 mosses, but require more heat and are therefore chiefly developed in 

 humid warm temperate districts. New Zealand is distinguished above 

 all other countries of the earth for the abundance of its ferns. Systemati- 

 cally the temperate fern-flora is less rich than that of the tropics, as it 

 is nearly or entirely devoid of several orders that occur in the tropics 

 and possesses no order peculiar to itself. The Cyathcaccac exhibit only 

 a few temperate species, which chiefly inhabit the southern warm temperate 

 belt ; their arborescent forms, although represented by a few species only, 

 are a principal constituent of the flora of Tasmania (Fig. 231) and of New 

 Zealand, less of that of South Africa. The Hymcnopliyllaccac exhibit 

 a similar reduction and similar distribution. The Polypodiaccae are much 

 more dominant in temperate zones than in the tropics. 



The Lyccpodiaccac and Equisctaccae play only a subordinate part in 

 the temperate zones. 



Gymnospermae. 



Abundance of gymnospernis and their wide distribution as socially 

 growing forest-trees distinguishes at the first glance the temperate from 

 the tropical flora. This important part is played only by Conifcrae'^. 

 Cycadaceae (Fig. 232) are far poorer in species and are rarer than in the 

 tropics, and the small family of Guctaccac is represented by a few species 

 of Ephedra alone. The most extensive coniferous forests arc those of 

 the cold belt of the north temperate zone; they consist almost exclusively 

 of Plnaceae (Pinus, Abies, Picea, Larix : in North America also Taxodium, 

 Sequoia ; in Japan also Cryptomeria) ; the Taxaceae (Taxus. Ginkgo) are 



' See p. 226. - See the distribution of Coniferae in Urude's .'Xtlas. No. II. I 



I 



