The fertilisation of flowers / by Prof. Hermann Müller, translated and edited by D'Arcy W. Thompson, with a preface by Charles Darwin.
- Hermann Müller
- Date:
- 1883
Licence: Public Domain Mark
Credit: The fertilisation of flowers / by Prof. Hermann Müller, translated and edited by D'Arcy W. Thompson, with a preface by Charles Darwin. Source: Wellcome Collection.
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![explanation of fertilisation, which, erroneous as it was, was not contro¬ verted until the appearance of SprengePs book and, afterwards still more thoroughly by F. J. Schelver1 and August Henschel.2 The researches of these botanists showed clearly that in most plants pollination of the pistil is impossible or at least improbable without the cooperation of some external agent. The last two authors, since they did not ascribe the proper importance to insect-visits, were led into the error of denying the sexuality of plants. On the other hand, Sprengel has not only rendered the negative service of showing, as the others did, how the prevalent conception of the mode of fertilisation is directly contrary to the actual relations, but also the positive service of removing the last objection to the sexual theory by his theory of the adaptation of flowers to fertilisation by insects.3 2. Even Sprengel notes several instances of incomplete adaptation ; e.g. on page 259, “Although the flowers (Lychnis dioica) being nocturnal are not adapted for humble-bees, yet these make use of their nectar.” 3. Perhaps F. G. Kurr has reviewed most thoroughly Sprengel’s observa¬ tions in his book Untersuchungen iiber die Bedeutung der Nektarien in den Blumen, which is replete with his own observations and ideas. But even this acute observer 4 lets us clearly trace how his ignorance of the advantage of cross-fertilisation prevented him from agreeing with Sprengel’s explanations, and how, along with SprengePs theories, he rejected his correct observations (e.g. in the case of Campanula) in order to cling to old errors. Severin Ax ell, in his above-mentioned work, cites the following later botanists who rejected SprengePs discoveries ; “ Treviranus,5 in upholding the sexuality of plants against Henschel, denies altogether that the organs of the two sexes mature at different times, and declares that the pollen and the stigma always ripen simultaneously ; Schultz-Schultzenstein6 attacks Sprengel, and charges him with false statements; Re Candolle7 asserts: ‘ M. Conrad Sprengel a cherclri a developper ses idees, plus fondees, je le crains, sur des theories metaphysiques que sur la simple observation des faits;’ Mikan criticises him for his description of the apparatus for fertilisation in the violet ; even Robert Caspary says, ‘ quod censeo, non injuste dici potest, inter omnes illas Sprengelii observationes, quas certissimas profert, quo modo insecta bores fecundent, ne imam quidarn esse, ex qua certe concludi possit, nullo alio modo flores fecundari quam auxiliis insectorum.’ Robert Brown alone, in his well-known paper (114) on the fertilisation of Asclepiadacece and Orchidacece conhrmed the accuracy of SprengePs statement that the aid of insects is necessary for the fertilisation of these plants, although he, like Sprengel, failed to notice that here cross-fertilisation occurs and not self-fertilisation.” Just as, according to these extracts, most botanists reviewed onesidedly the.weakness of SprengePs theory, nnd threw overboard the good along with the defective ; so, with equal onesidedness, Delpino and Severin Axell have 1 Kritik der Lclire von den GcschlecMern dcr PJlanzen (Heidelberg : 1812). 2 Von der Sexualitat (Breslau : 1820). 3 Of. Severin Axel], “ Ovi det fdrgade hyllcts betydelse for vaxten,” Bot. Notiser Tredje haftet, 1868. 4 Loc. cit. pp. 138, 139. 6 Die Lehre vom Geschleehle der PJlanzen (Bremen : 1822). 6 Die Fortyflanzung und Ernahrung der PJlanzen (1828). 7 Organographie vtgetale, i. p. 538 (Paris: 1827).](https://iiif.wellcomecollection.org/image/b29286487_0046.jp2/full/800%2C/0/default.jpg)
