38 



THE HOLLOW CURVE 



[CH. IV 



more villages, but always in diminishing numbers as one goes 

 upwards, just as with the plants. Most often the villages are in 

 the same neighbourhood, but at times they are as far off as a 



Monospecific Genera at this end of curve 



• C 



ft) ^ 

 . «■ "^ j- 





/June of Genera 

 ospp. 



Number of species (or size of area.J 



Fig. 5. Mixed curves, to show the close agreement of the hollow curves, 

 whether derived from families of plants grouped by sizes of genera (Com- 

 positae, Hymenomycetineae, Simarubaceae), families of animals (Chryso- 

 melidae, Amphipodous Crustacea, Lizards), endemic genera grouped by sizes 

 (Islands, Brazil, New Caledonia), local floras grouped by (local) sizes of genera 

 (Ceylon, Cambridgeshire, Italy), local faunas (Birds of British India, British 

 Echinoderms), Tertiary fossils by sizes of genera, or Endemic Compositae 

 of the Galapagos by area. [By courtesy of the Editor of Nature.] 



man can walk in one or two days, their distances and the tracks 

 on which they lie showing the directions of emigration of young 

 fellows in search of work. 



The distribution of species of plants that occurred in Ceylon, 



