18431882] AUSTRALIAN PLANTS 447 



able to the life of the introduced species. Hypothetically Letter 340 



I should rather look at the case as owing to but as my 



notions are not very simple or clear, and only hypothetical, 

 they are not worth inflicting on you. 



I had vowed not to mention my everlasting Abstract l to 

 you again, for I am sure I have bothered you far more than 

 enough about it ; but as you allude to its previous publication 

 I may say that I have chapters on Instinct and Hybridism to 

 abstract, which may take a fortnight each ; and my materials 

 for Palaeontology, Geographical Distribution and Affinities 

 being less worked up, I daresay each of these will take me 

 three weeks, so that I shall not have done at soonest till 

 April, and then my Abstract will in bulk make a small 

 volume. I never give more than one or two instances, and 

 I pass over briefly all difficulties, and yet I cannot make my 

 Abstract shorter, to be satisfactory, than I am now doing, and 

 yet it will expand to small volume. 



To J. D. Hooker. Letter 341 



Down, [Nov.?] 27th [1858]. 



What you say about the Cape flora's direct relation to 

 Australia is a great trouble to me. Does not Abyssinia 2 high- 

 land, and the mountains on W. coast in some degree connect 

 the extra-tropical floras of Cape and Australia? To my 

 mind the enormous importance of the Glacial period rises 

 daily stronger and stronger. I am very glad to hear about 



1 The Origiit of Species was abbreviated from the MS. of an un- 

 published book. 



3 In a letter to Darwin, Dec. 2ist (?), 1858, Sir J. D. Hooker wrote : 

 "Highlands of Abyssinia will not help you to connect the Cape and 

 Australian temperate floras : they want all the types common to both, 

 and, worse than that, India notably wants them. Proteaceas, Thymeleae, 

 Haemodoraceas, Acacia, Rutaceae, of closely allied genera (and in some 

 cases species), are jammed up in S.W. Australia, and C.B.S. [Cape of 

 Good Hope] : add to this the Epacrideae (which are mere of Ericaceae) 

 and the absence or rarity of Rosaceae, etc., etc., and you have an amount 

 [of] similarity in the floras and dissimilarity to that of Abyssinia and India 

 in the same features that does demand an explanation in any theoretical 

 history of Southern vegetation." 



Mr. Darwin's answer (Dec. 24th) to this letter is given in Life and 

 Letters, II., p. 142. He says: "With respect to South-West Australia 

 and the Cape, I am shut up, and can only d n the whole case." 



