Chap. II] 



GUILDS 



197 



Fig. i 10. Transverse section of stem of Securidaca 

 lanceolata, St.-Hil. Natural size. After H. Schenck. 



are unfavourable to the production of long axes 1 . The guild therefore 

 inhabits an enormous area, although it is very unequally distributed. In 

 by far the majority of cases, lianes are inhabitants of the tropics and of 

 a few neighbouring lands with 

 a tropical climate, such as 

 Southern Brazil and South 

 Florida. According to an 

 estimate, which H. Schenck 

 considers as probably too low, 

 about ten-elevenths or over 

 ninety per cent, of the lianes 

 are tropical. Even in the 

 tropics the distribution of 

 lianes is very unequal ; most 

 of the long woody forms 

 only appear in damp rain- 

 forests and monsoon-forests 2 , 

 whilst dry woodlands and 



savannahs produce hardly any but thin-stemmed and chiefly herbaceous 

 forms. 



Outside the tropics, lianes occur chiefly in temperate rain-forests in 

 Southern Japan, New Zealand, Southern Chili, more rarely and in less 

 variety in very damp summer-forests 3 in Central Japan, Atlantic and 

 Central North America, without showing anything like such variety as 

 in the tropics. 



2. EPIPHYTES 4 . 



Epiphytes are plants that germinate on other plants and grow without 

 obtaining nutriment at the cost of the substance of their host. In this 

 they differ from true parasites, with which they are often confounded. 



Their mode of life makes the acquisition of the necessary nourishment 

 a matter of difficulty, but starvation is not the chief danger to which 

 they are exposed. Epiphytes, attached as they are to the surface of other 

 plants, are more exposed to the danger of drought, and they are con- 

 sequently confined to regions where long persistent drought is unknown, 

 except when they have the faculty of existing in a desiccated condition, 

 a power which is possessed by many mosses and lichens, but which appears 

 to be altogether wanting in ferns and phanerogams, in spite of the ability 

 of a few species to withstand very considerable loss of water. The epiphytic 

 guild therefore exhibits, according to the nature of the climate, an in- 

 equality in systematic composition and in diversity and luxuriance of growth. 



Districts where a drying up of the plants owing to scarcity of water is 



1 See Part III, Sects. Ill and IV. 3 See Part III, Sect. I, Chap. III. 



2 See Part III, Sect. II. * Schimper, op. cit. 



