His experiments in hybridisation, of which he stored most exact accounts, exceeded the variety of 9 thousand ; in these and in regular instances of pollination he studied all of the sources of error which may in any means have an effect on his experiments, and took into careful consideration all the circumstances of fertilisation related with the development of the plant itself and with its external circumstances; at the identical time he examined critically all that had been written on the topic, and submitted each experiment reported by former observers to the take a look at of his personal wide expertise. Morson, who has herself reported extensively on sexual abuse within the Catholic Church, says it took years for her to realize that she too had been groomed by Pavone. Such was the character of the experiments to which Franz Joseph Schelver, Professor of Medicine in Heidelberg appealed in his ‘Kritik der Lehre von dem Geschlecht der Pflanzen,’ 1812. It’s unnecessary to give an in depth account of this unusual production of a mind misled, although a consider- able number of German botanists as late as 1820 took its nonsense for profound knowledge. But the entire physique of his outcomes, derived from the experimental researches of five-and-twenty years, were not published till 1849 and then in a big volume, ‘Versuche und Beobachtungen über die Bastardzeugung,’ Stuttgart, 1849, having been preceded by an introductory work of equal extent, ‘Versuche und Beobachtungen über die Befruchtungsorgane der vollkommeneren Gewachse und über die natürliche und ktinstliche Befruchtung durch den eigenen Pollen.’ The two works together are probably the most thorough and full account of experimental investigation into sexual relations in plants which had yet been written.

The second antennae, mandibles and two pairs of maxillae may also be claimed as of malacostracan kind. The extremity of the tube now swells out right into a spherical or oval form, and cell-tissue types from its contents; the lateral organs, one or two cotyledons, are then produced, the unique apical level remaining roughly free and forming the plumule. The portion of the tube underneath the embryo and the fold of the embryo-sac which envelopes it are divided off sooner or later and dis- appear, so that the embryo now actually lies within the embryo-sac.’ This view, which appears to relaxation on direct remark and is illustrated by figures which answer to the outline, corresponds with the outdated concept of evolution and has a putting approximation to the ideas of Morland and Geoffrey; and if it were correct, it could like these suggest the necessity of pollination to the formation of seeds that ought to include embryos, however at the identical time it would dispose of that which is the essential level in the sexuality of plants, for the ovule would merely be the spot adapted to the hatching of the embryo formed from the pollen. With regard to phenomena of this form botanists earlier than 1860 had been in a position, wherein they were with out the means of forming a judgment; they shrank from the teleological point of view and from believing with Konrad Sprengel, that every, even the least-apparent, arrangement in an organism was the direct work of a Creator; however they had nothing higher to put within the place of this idea, and therefore Sprengel’s discoveries not being understood had been uncared for until Darwin recognised all their importance, and by opposing the theory of descent and choice to the principle of design was ready not only to point out that that they had a scientific meaning, but also to employ them as highly effective supports of the theory of choice.

Robert Brown showed in 1831 and 1833 that the grains in the pollen-lots of Orchids and Asclepiads put forth pollen-tubes as in different plants, and that positive tubes are found within the ovary of Orchids through which pollination has taken place; but he was in doubt about the connection of these tubes with the pollen-grains, and fairly inclined to suppose that they were formed in the ovary, although probably in consequence of the pollination of the stigma. Amici, who was inspecting the hairs on the stigma of Portulaca for an additional goal, saw on that occasion (1823) the pollen-tube emerge from the pollen-grain, and the granular contents of the latter, generally known as the fovilla, execute streaming movements just like the well-known movement in Chara. But in the following year (1846) Amici produced decisive proof for the views which he had maintained; he showed from the Orchidaceae, which have been peculiarly properly adapted for such investigations, not solely that Robert Brown’s doubts above mentioned were with out basis, but, which is the main level, that a body, the egg-cell, is present in the embryo-sac of the ovule before the arrival of the pollen-tube, and that this physique is excited by the presence of the pollen-tube to additional improvement, the formation of the embryo.

Gartner’s work on hybridisation had been preceded by other enquiries into the identical topic, these particularly of Knight talked about above in the beginning of the century, and Herbert’s extra ample investigations printed in his work on Amaryllideae in 1837. Gärtner did not neglect to compare his observations in any respect factors with the outcomes of his predecessors, especially those of Koelreuter, and he deduced from the astonishing mass of material quite a lot of common propositions respecting the circumstances under which the manufacturing of hybrids is feasible, the outcomes of crossing, and the causes of failure. The destructive effects of the nature-philosophy on the powers of the understanding at first of the nineteenth century was shown in the case of many botanists, who had been now not able to estimate the result of straightforward experiments, and to hint again the phenomena of nature to the scheme of causes and effects. But Koelreuter was imperfectly acquainted with the strategies by which pollination is often effected in nature; Sprengel was the first who noticed into all their extra essential relations, and the fact should not be hid, that Gärtner in regarding Konrad Sprengel’s observations as unworthy of serious consideration, neglected probably the most fruitful supply of new and magnificent results.