246 Transactions. — Botany. 



the question cannot be satisfactorily answered yet ; our knowledge of the 

 subject is of too fragmentary and incomplete a nature. Mr. A. E. Wallace, 

 who may be considered one of the most leading authorities on such a ques- 

 tion, concludes that the poverty of insect life here is one of the chief causes. 

 He says* — and I must be pardoned for quotmg his opinion at some length — 

 " In New Zealand, where insects are so strikingly deficient in variety, the 

 flora is almost as strikingly deficient in gaily-coloured blossoms. Of course 

 there are some exceptions, but, as a whole, green, inconspicuous, and im- 

 perfect flowers prevail to an extent not to be equalled in any other part of 

 the globe, and affording a marvellous contrast to the general brilliancy of 

 Australian flowers, combined with the abundance and variety of its insect- 

 life. We must remember, too, that the few gay or conspicuous flowering- 

 plants possessed by New Zealand are almost all of Australian, South Ameri- 

 can, or European genera ; the peculiar New Zealand or Antarctic genera 

 being almost wholly without conspicuous flowers.! * ■■' * The 

 poverty of insect-life in New Zealand must, therefore, be a very ancient 

 feature of the country ; and it furnishes an additional argument against the 

 theory of land-connection wdth, or even any near approach to, either Aus- 

 tralia, South Africa, or South America. For in that case numbers of 

 winged insects would certainly have entered, and the flowers would then, as 

 in every other part of the world, have been rendered attractive by the 

 development of coloured petals ; and this character once acquired would 

 long maintain itself, even if the insects had from some unknown cause 

 subseq\iently disappeared." " After the preceding paragraphs were written, 

 it occurred to me that, if this reasoning were correct, New Zealand plants 

 ought to be also deficient in scented flowers, because it is a part of the same 

 theory that the odours of flowers have, lilie their colours, been developed to 

 attract the insects required to aid in their fertilization. I therefore at once 

 applied to my friend, Dr. Hooker, as the highest authority on New Zealand 

 botany ; simply asking whether there was any such observed deficiency. 

 His reply w^as, — ' New Zealand plants are remarkably scentless, both in 

 regard to the rarity of scented flowers, of leaves with immersed glands con- 

 taining essential oils, and of glandular hairs.' There are a few exceptional 

 cases, but these seem even more rare than might be expected, so that the 



* " The Geographical Distribution of Animals," Vol. I., pp. 457-464. 



t The following exclusively New Zealand or Antarctic genera are surely exceptions : 

 Notothlaspi (white), Hectorella (white), Hoheria (white), Entelea (white), I'ennantia (white), 

 Notospartium (pink), Ixerha (white), Stilbocarpa (yellowish), Corokia (yellow), Pleuro- 

 phyllum (purple), Raoulia (white), Helophyllum (white), Colensoa (blue), Myosotidium 

 blue), Rhahdothamnus (reddish), Earina (white and yellow), and Phormium (reddish). 

 All these are more or less entomophilous. 



