Chap. VI] ANIMALS 129 



the New Zealand flora as consisting of almost exclusively inconspicuous, 

 greenish, scentless flowers, and he connected the supposed absence of 

 brightly coloured or scented flowers with the supposed rarity of insects. 

 Actually however neither beautifully coloured flowers, nor insects with 

 well-developed senses of colour and smell, are so rare in New Zealand 

 as Wallace assumed. 



Of 433 flowering plants of New Zealand, according to G. M. Thomson, hardly 

 half (49 %) have inconspicuous flowers, and 22 % are scented. Over 23 % of the species 

 are adapted for cross-pollination by insects, 48 % are fertile when self-pollinated, 

 and 29 % are anemophilous. Diptera are here the most important pollinators ; 

 the inconspicuous entomophilous flowers are hardly ever, if at all, visited by other 

 insects. In addition many of the numerous beetles (about 1,300 species) take 

 part in pollination. Among Lepidoptera the numerous Noctuidae are of greater 

 importance than the few butterflies (18 species). There are only 10 species of 

 bees. Finally, birds are the chief or exclusive pollinators of many large flowers. 

 The sole inference to be drawn from this description is that the relatively large 

 number of inconspicuous flowers possibly may be connected with the predominance 

 of Diptera. 



Whilst most insular floras are remarkable for their poverty in plants 

 with beautiful flowers, the small archipelago of Juan Fernandez, on the 

 contrary, is distinguished by the splendour of its flower-tints ; frequently 

 the flowers of indigenous species are even more conspicuous than those 

 of allied continental species. According to Wallace, the beautiful colours of 

 the flowers have been induced through selection by two endemic species of 

 humming-birds. Johow. who was able to study on the spot the oecology 

 of the vegetation of Juan Fernandez, considers as highly probable the 

 pollination of many species by humming-birds, for instance Rhaphithamnus, 

 Escallonia, Myrceugenia fernandeziana ; he however states, on the other 

 hand, that the scarcity of insects is not nearly so great as Wallace 

 appears to have assumed. Thus, various Lepidoptera are extraordinarily 

 numerous, and Diptera were observed by Johow on the flowers of 

 Dendroseris, Robinsonia, and Eryngium bupleuroides amongst others. 

 Wallace's view, although generally adopted, should not command scientific 

 acceptation until it has been confirmed by observations made on the spot. 



Only careful and prolonged observations will be able to demonstrate 

 the significance of the pollination of flowers in regard to the composition 

 and physiognomy of insular floras. In the case of some islands of the 

 North Sea, near the coast, observations have recently, been made by 

 Behrens, Verhoeff, Alfken, and Knuth, from which there is a promise 

 of useful results. These islands indeed have no indigenous forms, and 

 are, in many respects, less interesting than oceanic islands ; but their 

 recent formation, their proximity to the continent, and the obvious origin 

 of their flora and fauna, appear to fit them for explaining many differences 



