iS68-t88i] HARVESTING A NTs 5,1 



To J. Traherne Moggridge. Utter 712 



I town, March 10th, 1S74 



I am very sorry to hear that the vapour experiments have 

 failed; but nothing could be better, as it seems to me, than 

 your plan of enclosing a number of the ants with the • 

 The incidental results on the power of different vapours in 

 killing seeds and stopping germination appear very curi. 

 and as far as I know are quite new. 



P.S. — I never before heard of seeds not germinating 

 except during a certain season ' ; it will be a very strange 

 fact if you can prove this. 



To H. Miiller. , cr 



I lown, May 30th, 1S73. 

 I am much obliged for your letter received this morning. 

 I write now chiefly t" give myself the pleasure of telling you 

 how cordially I admire the last part of your book, 2 which I 

 have finished. The whole discussion seems to me quite 

 excellent, and it has pleased me not a little to find that in 

 the rough MS. of my last chapter 3 I have arrived on many 

 points at nearly the same conclusions that you have done, 

 though we have reached them by different routes. 



To F. Delpino. 



Down, June 25th [1873]. Letter 7 '* 



I thank you sincerely for your letter. I am very glad to 

 hear about Lathyrus odoratus, for here in England the vars. 

 never cross, 4 and yet are sometimes visited by bees. Pisum 

 sativum I have also many times seen visited by Botnbus, 

 I believe the cause of the man}- vars. not crossing is th 

 under our climate the flowers are self-fertilised at an early 



1 Certain seeds pass through a resting period before germination. 

 See Pfeffer's Pflamenphysiologie, Ed. 1.. Vol. II., p. in. 



1 " Die Befruchtung der Blumen durch Insekten " : Leipz ;. An 



English translation was published in 1883 by Prof. D'Arcy Thompson. 

 The "Prefatory Notice " to this work (Feb. 6th, [882) is almost the last 

 of Mr. Darwin's writings. See Life and p. 281. 



3 The Effects of Cross and Self-Fertilisation it n; 

 London, 1876. 



4 In Cross and Self-Fertilisation, p. 156, Darwin quotes the informa- 

 tion received from Delpino and referred to in the present letter- namely, 

 that it is the fixed opinion of the Italian gardeners that the varieties do 

 intercross. See Letter 709. 



