Thanks CD for the English edition of his brother's book [Fritz Müller, Facts and arguments for Darwin (1869)]
and for CD's memoir on orchids ["Fertilization of orchids", Collected papers 2: 138–56].
22. Sept. 1869.
My dear Sir
I am very much obliged to you for your kindness in having sent me the translation of my brothers book and recently your memoir on Orchids, which I have read all two with the greatest interest. I beg leave to thank you for the kind and very honorable mention which you make of my observations on Orchids.
Last spring I have succeeded to observe repeatedly the fertilisation of Orchis mascula by different species of Bombus. I have described in detail my observations in a report which will be printed in the ``Verhandlungen des naturhist Vereins etc'' and which I shall send you as soon as I have received separata.
All my leisure-time during the last summer has been bestowed upon insects visiting and fertilizing flowers. Until next summer passed I hope to can finish preliminarely and publish these observations
With sincere thanks and respect I remain my dear Sir | yours very faithfully | H Müller.
- f1 6904.f1The references are to Fritz Müller's Facts and arguments for Darwin (Dallas trans. 1869) and `Fertilization of orchids'.
- f2 6904.f2Müller's observations are cited in `Fertilization of orchids', pp. 142, 147, 150, 152, 156 (Collected papers 2: 139, 144, 147, 149, 153).
- f3 6904.f3Müller's paper `Die Anwendung der Darwin'schen Lehre auf Blumen und blumen-besuchende Insekten' (The application of Darwinian theory to flowers and flower-visiting insects; H. Müller 1869) was published in the Verhandlungen des naturhistorischen Vereines der preussischen Rheinlande und Westphalens. CD's annotated copy is in the Darwin Pamphlet Collection--CUL. In `Fertilization of orchids', p. 142 (Collected papers 2: 139), CD had noted that flowers of Orchis mascula (the early purple orchid) were visited by Bombus muscorum (the large carder bee), adding that insects were seldom seen visiting this species. For Müller's observations on visits to O. mascula by three different species of Bombus (bumblebees) as well as other insects, see H. Müller 1869, pp. 52--5.