" The farina of the Corona Soils perennls, Flore et Semlne maxlmls, Hort. Ludg. Bat. is a globe set with thorns ; that of the Ricinus 

 Vulgaris, C. B. P. is of the figure of a grain of Wheat. 



" And the Acer Montanum Candldum of C B. P. affords a dust of the figure of a cross: and in like manner does the farina of every 

 plant differ in its shape from the rest. 



" The female organs of generation in plants are best seen in large fruits, without the trouble of the microscope ; such as the fruit of the 

 Pomplon or Melon, where, with the natural eye, we may discover the vessels distinctly, which make the tunic or covering of each ovary : 

 Ave may see how the seeds are joined to it, and by what end they receive their nourishment. And again, between the several ovarie's 

 enclosed in that fruit, we may very easily perceive the hollow, or passage, through which the farina fcecundans has passed to impregnate 



the seeds. 



" It may perhaps be objected against this hypothesis, that there are many flowers which hang downwards, as the Crown Imperial, the 

 Cyclamen, &c. and that their pistils cannot receive the farina fcecundans upon them : but if we observe that the pistils of these flowers are 

 always more prominent, or somewhat longer than the dusty apices which surround them, we may easily conceive that the glutinous matter 

 and velvet covering on the extremities of the pistils, may be capable enovigh of receiving and holding some of the powder as it falls ; and 

 whether the intromission of the farina facundans be requisite or not, its lodgment on the mouth of the pistillum may, by virtue of its at- 

 tractive quality, perhaps fecundate the seeds contained in the germen : I am sure, in the production of animals, there are yet greater difficul- 

 ties to encounter with ; and it may be, if the analogy between plants and animals was more enquired after by the learned, they might dis- 

 cover many new things which would be serviceable to the preservation and benefit of animal bodies, as this knowledge will be to the im- 

 provement of the vegetable world. 



" I shall now proceed to what I call the demonstrative part of this system. I made my first experiment upon the tulip, which I chose 

 rather than any other plant, because it seldom misses to produce seed. Several years ago I had the conveniency of a large garden, wherein 

 there was a considerable bed of tulips in one part, containing about four hundred roots: in another part of it, very remote from the former, 

 were twelve tulips in perfetl health. At the first opening of the twelve, which I was very careful to observe, I cautiously took out of them 

 all their apices (anthers), before the farina fcecundans was ripe, or any ways appeared: these tulips being thus castrated, bore no seed that 

 summer; while, on the other hand, every one of the four hundred plants, which I had let alone produced seed." 



Blair, in his " Botanical Essays," in that " On the Generation of Plants," has collected the opinions of all former writers, and added his 

 own, in refutation of the embryo being constituted in the particles of farina. He has added no experiments of his own on the Sexes of 

 Plants. 



Next follows our illustrious Miller, in the Gardener's Dictionary, published in 1/30, under the word '' Generation." After detailing 

 the different sentiments and opinions advanced on this subject, he ends by relating his own experiments. 



" I shall conclude with mentioning a few experiments of my own, which I communicated to Dr. Patrick Blair, which he improved as a 

 proof of his opinion of effluvia ; and Mr. Bradley also, as a proof of the farina entering the germen in substance, and leave the curious enquirer 

 to determine on that side of the question, which reason and experiment shall influence him. 



" [ separated the male plants of a bed of spinage from the female, and the consequence w^as, that the seed did swell to the usual bigness; 

 but when sowed, it did not grow afterwards : and searching into the seed, I found it wanted the Punctum Vita. 



" I set twelve tulips by themselves, about six or seven yards from any other; and as soon as they blew, I took out the stamina so very 

 carefully, that I scattered none of the male dust; and about two days afterwards I saw bees working on a bed of tulips, where I did not take 

 out the stamina ; and when they came out, they were loaded with dust on their bodies and legs, and I saw them fly to the tulips, where I 

 had taken out the stamina ; and when they came out, I found they had left behind them sufficient to impregnate these flowers, for they bore 

 good ripe seeds. But by a piece of gauze put over the flowers the experiment is found to answer. 



" In a letter communicated by Paul Dudley, Esq. to the Royal Society, wrote from New England, he mentions the interchanging of the 

 colours of the Indian wheat, if the various colours are planted in rows near each other ; but if they are planted separately, they constantly 

 keep to their own colour: and this interchanging of colours has been observed, when the distance between the rows of corn has been several 

 yards; though he says, if there happens to be a high board fence between the different coloured corns, the alteration of colours is entirely 

 prevented. 



Cucumbers do always produce male and female flowers upon different parts of the same plant : the male flower (which appears upon a 

 slender footstalk, and has a slender column in the middle, covered with an orange-coloured farina) is by the gardeners commonly called 

 false blossoms, and are sometimes by unskilful persons pulled off soon after they appear, supposing that they weaken the plants if suffered to 

 remain, which is a very great mistake : for in order to try this experiment, I planted four rowss ot cucumber plants in a place pretty far distant 

 from any other; and when the flowers began to appear, I constantly pulled off all the male flowers from time to time before they opened: 

 the consequence was, that all the young fruit dropt off soon after they appeared, and not one single fruit remained to grow to any size, 

 though the vines were equally strong with those which I had planted in another place, where I suffered all the flowers to remain upon them, 

 from which I had a great quantity of fruit. 



" From these, and many other experiments, it is very plain, that there is a neceflity that the embryo of the female flower should be im- 

 pregnated by the farina or male dust, in order to render the fruit perfect ; but how, or in what manner it is performed, is what we can only 

 guess at, since in the generation of animals, our greatest naturalists differ very much in their opinions, nor can any of them ascertain any 

 particular method how it is performed. 



" Some persons have objected to the theory of the generation, as here laid down, because they have observed some female plants produce 

 fruit, without having been impregnated by the male. 



" It is certain, that the female plants may produce fruit without the impregnation of the male ; but it is not certain, that this fruit or 

 seed will, if sown, produce another plant. What has been so often related by travellers and historians, of the necessity of the male palm- 

 tree being near the female, in order to render it fruitful, hath been, it is supposed, fully refuted by Father Labat, in his account of Africa, 

 where he has treated of the several sorts of palms : he says, that he observed, in Martinico, a large palm-tree, which grew by the side of a 

 convent, which produced fruit in plenty, though there was no other palm-tree growing within two leagues of this ; but he also observed, that 

 none of these fruit would grow, though they had made many trials of them ; so that they were obliged to procure some fruit from Barbary, 

 in order to propagate these trees. He likewise adds, that the fruit which grew on this female tree, never ripened so perfectly, nor was so 

 well tasted, as those which came from trees which had stood near some of the male. Therefore we may conclude, that the fruit or seed may 

 be produced by the female plants of most kinds, without the assistance of the male sperm, which may appear to sight perfect, and fit to 

 produce other plants ; but if we examine the seeds, we shall find that most of them have not the germ, or little plant inclosed, nor will 

 grow, if they are sown. 



e " From 



