18591863] ARCTIC PLANTS 155 



To C. Lyell. Letter 106 



Down [June?J 20th [1860]. 



I send Blyth l ; it is a dreadful handwriting ; the passage 

 is on page 4. In a former note he told me he feared there was 

 hardly a chance of getting money for the Chinese expedition, 

 and spoke of your kindness. 



Many thanks for your long and interesting letter. I 

 wonder at, admire, and thank you for your patience in writing 

 so much. I rather demur to Deinosaurus not having " free 

 will," as surely we have. I demur also to your putting 

 Huxley's " force and matter " in the same category with 

 Natural Selection. The latter may, of course, be quite a 

 false view ; but surely it is not getting beyond our depth 

 to first causes. 



It is truly very remarkable that the gestation of hounds 2 

 should vary so much, while that of man does not. It may 

 be from multiple origin. The eggs from the Musk and the 

 common duck take an intermediate period in hatching ; but 

 I should rather look at it as one of the ten thousand cases 

 which we cannot explain namely, when one part or function 

 varies in one species and not in another. 



Hooker has told me nothing about his explanation of few 

 Arctic forms ; I knew the fact before. I had speculated on 

 what I presume, from what you say, is his explanation 3 ; but 



1 See Letter 27. 



2 In a letter written to Lyell on June 25th, 1860, the following 

 paragraph occurs : " You need not believe one word of what I said about 

 gestation of dogs. Since writing to you I have had more correspondence 

 with the master of hounds, and I see his [record ?] is worth nothing. It 

 may, of course, be correct, but cannot be trusted. I find also different 

 statements about the wolf: in fact, I am all abroad." 



3 " Outlines of the Distribution of Arctic Plants," J. D. Hooker, Trans. 

 Linn. Soc., Vol. XXIIL, p. 251, 1862. [Read June 2ist, 1860.] In this 

 paper Hooker draws attention to the exceptional character of the Green- 

 land flora ; but as regards the paucity of its species and in its much 

 greater resemblance to the floras of Arctic Europe than to those of 

 Arctic America, he considers it difficult to account for these facts, 

 "unless we admit Mr. Darwin's hypotheses" (see Origin, Ed. vi., 1872, 

 Chap. XII., p. 330) of a southern migration due to the cold of the glacial 

 period and the subsequent return of the northern types during the suc- 

 ceeding warmer period. Many of the Greenland species, being confined 

 to the peninsula, " would, as it were, be driven into the sea that is 

 exterminated" (Hooker, op. cit., pp. 253-4). 



