18431882] INSULAR FLORAS 491 



To J. D. Hooker. Letter 374 



Dec. 24th [1866]. 



. . . One word more about the flora derived from supposed 

 Pleistocene antarctic land requiring land intercommunication. 

 This will depend much, as it seems to me, upon how far 

 you finally settle whether Azores, Cape de Verdes, Tristan 

 d'Acunha, Galapagos, Juan Fernandez, etc,, etc., etc., have 

 all had land intercommunication. If you do not think this 

 necessary, might not New Zealand, etc., have been stocked 

 during commencing Glacial period by occasional means from 

 antarctic land ? As for lowlands of Borneo being tenanted 

 by a moderate number of temperate forms during the Glacial 

 period, so far [is it] from appearing a "frightful assumption' 

 that 1 am arrived at that pitch of bigotry that I look at 

 it as proved ! 



J. D. Hooker to C. Darwin. Letter 375 



Kew ; Dec. 25th, 1866. 



I was about to write to-day, when your jolly letter came 

 this morning, to tell you that after carefully going over the 

 N. Z. Flora, I find that there are only about thirty reputed 

 indigenous Dicot. annuals, of which almost half, not being 

 found by Banks and Solander, are probably non-indigenous. 

 This is just oVth of the Dicots., or, excluding the doubtful, 

 about TVh, whereas the British proportion of annuals is ~ 



amongst Dicots. ! ! ! Of the naturalised New Zealand plants 

 one-half are annual ! I suppose there can be no doubt but 

 that a deciduous-leaved vegetation affords more conditions 

 for vegetable life than an evergreen one, and that it is hence 

 that we find countries characterised by uniform climates to be 

 poor in species, and those to be evergreens. I can now work 

 this point out for New Zealand and Britain. Japan may be 

 an exception : it is an extraordinary evergreen country, and 

 has many species apparently, but it has so much novelty that 

 it may not be so rich in species really as it hence looks, and 

 I do believe it is very poor. It has very few annuals. Then, 

 again, I think that the number of plants with irregular 

 flowers, and especially such as require insect agency, 

 diminishes much with evergreenity. Hence in all humid 

 temperate regions we have, as a rule, few species, many 

 evergreens, few annuals, few Leguminosae and orchids, few 



