320 BOTANY [Chap. X 



Letter 644 To John Scott. 



Down, May 25th, 1863. 



Now for a few words on science. I do not think I could 

 be mistaken about the stigma of Bolbophyllum l ; I had the 

 plant alive from Kew, and watched many flowers. That is a 

 most remarkable observation on foreign pollen emitting tubes, 

 but not causing orifice to close 2 ; it would have been interest- 

 ing to have observed how close an alliance of form would 

 have acted on the orifice of the stigma. It will probably be 

 so many years, if ever, [before] I work up my observations on 

 Drosera, that I will not trouble you to send your paper, for I 

 could not now find time to read it. If you have spare copy 

 of your Orchid paper, please send it, but do not get a copy of 

 the journal, for I can get one, and you must often want to 

 buy books. Let me know when it is published. I have been 

 glad to hear about Mercurialis, but I will not accept your 

 offer of seed on account of time, time, time, and weak health. 

 For the same reason I must give up Primula mollis. What a 

 wonderful, indefatigable worker you are ! You seem to have 

 made a famous lot of interesting experiments. D. Beaton 

 once wrote that no man could cross any species of Primula. 

 You have apparently proved the contrary with a vengeance. 

 Your numerous experiments seem very well selected, and you 

 will exhaust the subject. Now when you have completed 

 your work you should draw up a paper, well worth publishing, 

 and give a list of all the dimorphic and non-dimorphic forms. 

 I can give you, on the authority of Prof. Treviranus in Bot. 

 Zeitung, case of P. longiflora non-dimorphic. I am surprised 

 at your cowslips in this state. Is it a common yellow cow- 

 slip ? I have seen oxlips (which from some experiments I 

 now look at as certainly natural hybrids) in same state. If 

 you think the Botanical Society of Edinburgh would not do 



1 Bolbophyllum is remarkable for the closure of the stigmatic cavity 

 which comes on after the flower has been open a little while, instead 

 of after fertilisation, as in other genera. Darwin connects the fact with 

 the " exposed condition of the whole flower." — Fertilisation of Orchids, 

 Ed. 11., p. 137. 



2 See Scott, Bot. Soc. Edin., 1863, p. 546, note. He applied pollinia 

 from Cypripedium and Asclepias to flowers of Trichopilia tortilis ; and 

 though the pollen germinated, the stigmatic chamber remained open, 

 yet it invariably closes eighteen hours after the application of its 

 own pollen. 



