To Daniel Oliver 12 [October 1860]1
15 Marine Parade | Eastbourne
My dear Sir
The Drosera & leaves of Dionæa. arrived quite safe. I am very much interested by them.— Pray give my best thanks to Sir William, & accept them yourself.—2
I am very busy & get my constant enemy headach; so will not write any more, but I have got a good deal to say first day I can.
Will you try one easy experiment.— Drop on sensitive hair of Dionæa one drop gently of pure water; & get solution of Carbonate of Ammonia 6 six gr. to 2 two oz of distilled water, & drop this & see if it immediately or within hour or two causes movement. This will not injure leaf.— Perhaps safer to get 4 gr to 2 oz water3 Also one drop of the C. of Ammonia on disc of leaf.— I want so much to know whether movement analogous of Dionæa & Drosera.—4
Yours very truly | C. Darwin
Requests DO apply carbonate of ammonia to sensitive hair of Dionaea and measure reaction time. Wants to compare Drosera and Dionaea.
Please cite as
Darwin Correspondence Project, “Letter no. 2946,” accessed on 24 October 2016, http://www.darwinproject.ac.uk/DCP-LETT-2946