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Updated: June 4, 2025
With respect to the difference in the corolla of the central and exterior flowers of a head or umbel, I do not feel at all sure that C. C. Sprengel's idea that the ray-florets serve to attract insects, whose agency is highly advantageous in the fertilisation of plants of these two orders, is so far-fetched, as it may at first appear: and if it be advantageous, natural selection may have come into play.
Fertilisation and cross-fertilisation are important ends enough to lead to any modification, but can we suppose mere nourishment to be so important, seeing that it is so easily and almost universally obtained by extrusion of roots and leaves? Here are plants which lose their roots and leaves to acquire the same results by infinitely complex modes!
Parlement exists no longer, or rather is expanded into a National Assembly that is a discredit to all France, and not Provence alone; the Durance has become, thanks to Adam de Craponne, an agent of fertilisation and wealth. In 1845 it carried away the suspension bridge between Beaucaire and Tarascon; the passage of the Rhone is often rendered impossible for days, through its violence.
He who will carefully examine the flowers of orchids for himself will not deny the existence of the above series of gradations from a mass of pollen-grains merely tied together by threads, with the stigma differing but little from that of the ordinary flowers, to a highly complex pollinium, admirably adapted for transportal by insects; nor will he deny that all the gradations in the several species are admirably adapted in relation to the general structure of each flower for its fertilisation by different insects.
Of the other chief organs we have still to mention the sexual glands, which lie right behind in the body-cavity. All the Ascidiae are hermaphrodites. Each individual has a male and a female gland, and so is able to fertilise itself. Fertilisation is accomplished here, and in many of the Ascidiae developed embryos are found.
In the maturation divisions reduction does not occur, N chromosomes passing to one gamete, none to the other, and the latter perishes so that the sperms all contain N chromosomes. When fertilisation occurs the zygote therefore contains 2N chromosomes and becomes female. Here then we have no segregation of Fxf in the ova.
If she had devoted half the genius she lavishes on crossed fertilisation and other arbitrary desires to making life more certain, to alleviating pain, to softening death and warding off horrible accidents, the universe would probably have presented an enigma less incomprehensible, less pitiable, than the one we are striving to solve.
On May 15th, 1862, my little book on the 'Fertilisation of Orchids, which cost me ten months' work, was published: most of the facts had been slowly accumulated during several previous years.
Well, it seems that there are lots of orchids known the flower of which cannot possibly be used for fertilisation in that way. Some of the Cypripediums, for instance; there are no insects known that can possibly fertilise them, and some of them have never been found with seed." "But how do they form new plants?" "By runners and tubers, and that kind of outgrowth. That is easily explained.
They maintain themselves there by clinging to the hairs. At the moment of fertilisation the male, thus burdened, comes in contact with the female; the coleopterous larvæ then pass on to her, so that, according to Fabre's expression, the meeting of the sexes brings death and life to the eggs at the same time.
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