Chapter 333

(672/1. In Darwin's book on Climbing Plants, 1875 (672/2. First given as a paper before the Linnean Society, and published in the "Linn. Soc. Journ." Volume IX.,), he wrote (page 205): "The conclusion is forced on our minds that the capacity of revolving, on which most climbing plants depend, is inherent, though undeveloped, in almost every plant in the vegetable Kingdom"--a conclusion which was verified in the "Power of Movement in Plants." The present letter is interesting in referring to Fritz Muller's observations on the "revolving nutation," or circumnutation of Alisma macrophylla and Linum usitatissimum, the latter fact having been discovered by F. Muller's daughter Rosa. This was probably the earliest observation on the circumnutation of a non-climbing plant, and Muller, in a paper dated 1868, and published in