58 



HISTORY OF THE VEGETABLE KINGDOM. 



the subject might be still farther illustrated by 

 means of depriving the plant of its male flowers 

 altogether, or of removing the individuals of 

 different sexes to a distance from one another. 

 Accordingly, having selected some plants, and 

 stripped them of their stamens or male organs, 

 or separated the male flowers entirely from the 

 female, he found that the fruit did not nowripen ; 

 the inference from which was, that the genera- 

 tion of plants is analogous to that of animals, 

 and that the stamens of the flowers of the 

 former correspond to the sexual organs of the 

 males of the latter. 



But though the fact of the sexuality of vege- 

 tables seemed thus unequivocally ascertained, 

 the peculiar mode of their fecundation was stiU 

 left undetermined. Some conjectures had been 

 offered with respect to it by Cesalpinus and 

 Grew, the former regarding it as being effected 

 by means of an exhalation from the male flower, 

 and the latter by means of an effluvium from 

 the pollen ; but Moreland, who published a paper 

 on the subject, in the Philosophical Transactions 

 for 1703, in which, indeed, he adopts the opinions 

 of Grew with regard to the functions of the 

 stamens, contends however, that the pollen is a 

 congeries of seminal plants, one of which, at 

 least must be conveyed tlu'ough the style into 

 the ovary, before it can become prolific. This 

 conjecture seems to have arisen out of the theory 

 of Leuwenhoeck on animal generation, which 

 was then popular; but it is not coiToborated 

 by any experiments. It seems, however, to have 

 had the effect of keeping alive the discussion of 

 the subjects. For Geofiroy, in his memoir pre- 

 sented to the Royal Academy of Sciences in 1711, 

 on the structure and use of the principal parts 

 of the flowers, endeavours, as it appears, to re- 

 concile the discordant theories of Grew and 

 Moreland, and maintains that the germ is never 

 visible in the seed tOl the anthers have shed their 

 poUen, adding, that if the stamens are cut off 

 before the anthers burst, the seeds remain barren. 

 In this we have a step in advance beyond the 

 point that had been gained by means of the ex- 

 periments of Camerarius, which relate only to 

 monoecious and dioecious plants, in which the 

 proof is less difScult than in hermaphrodites, to 

 which Geoffrey's experiments apply. From the 

 spirit of inquiry which was thus excited, new 

 discoveries could not but be expected to follow ; 

 for although the doctrine was discountenanced 

 and rejected by some of the leading botanists of 

 the time, and even by the illustrious Tournefort, 

 yet it was too well established in fact to be over- 

 thrown by any argument, or any authority. 

 Accordingly, its evidence was becoming every 

 day more in-esistible, and its advocates more 

 confident. Vaillant in a dissertation on the 

 structure of flowers, read at the opening of the 

 Royal Garden at Paris, in 1717, supports the 



doctrine of the sexes of vegetables by new ac- 

 cessions of experiments, and throws additional 

 light both on the structure of the pollen and 

 manner of its expulsion, which he represents, 

 however, in terms too glowing for the style of 

 sober naiTative, but 1 ly which he appears, accord- 

 ing to the remarks of a, contemporary author, 

 to have been the first eye witness of that secret 

 operation of nature, " the loves of the plants." 



But the doctrine of the sexes of vegetables which 

 was thus daily acquiring new accessions of proof, 

 was destined to receive its last degree of eluci- 

 dation from the pen of Linnsus. This great 

 and illustrious botanist, reviewing with his usual 

 sagacity the evidence on which the doctrine 

 rested ; and perceiving that it was supported by 

 a multiplicity of the most incontrovertible facts, 

 resolved to devote his labours peculiarly to the 

 investigation of the subject, and to prosecute 

 Ills inquiries throughout the whole extent of the 

 vegetable kingdom ; which great and arduous 

 enterprise he not only undertook, but accom- 

 plished Aiith a success equal to the unexampled 

 industry with which he pursued it. So that, by 

 collecting into one body all the evidence of former 

 discovery or experiment, and by adding much 

 that was original of his ovs-n, he found himself 

 at length authorised to dravv the important con- 

 clusion, — that no seed is perfected without the 

 previous agency of the pollen, and the doctrine 

 of the sexes of plants is consequently founded 

 on fact. It may not be deemed uninteresting 

 here, to give a brief summary of the facts and 

 deductions which led to this important con- 

 clusion. 



In all plants hitherto discovered, it has been 

 observed that the fruit is uniformly preceded by 

 the blossom, and that without blossom there 

 is no fruit. This is a remark that can scarcely 

 fail to be made even by the most inattentive ob- 

 server, at least with regard to such plants as 

 come within the sphere of his notice, as every 

 school boy knows, that unless the cheny tree 

 blossoms in spring, he wiU gather no fi-uit from 

 it in summer. This proves that the organs ne- 

 cessary to the production of the fruit exist in 

 the flower, and is one step at least towards the 

 general conclusion. But to this rule there exists 

 a seeming exception, in the case of the meadow 

 saffron, which produces its fruit in the spring, 

 and its flower in the autumn, so that the former 

 has the appearance of being the cause of the 

 latter. But the truth is, that the fruit which 

 ripens in the spring is the natural result of the 

 flower of the preceding autumn ; for if the flower 

 is cut off in autumn before its expansion, no 

 fruit wiU be produced in the succeeding spring, 

 and yet, if the fruit is cut off at any time during 

 spring, the blossom, nevertheless, succeeds in 

 autumn. There exists also another seeming 

 exception in the case of the pine apple, in which 



