CAMERARIUS, * and several others after him, f have well explained this doctrine : 



* Camerarius, Professor at Tubingen, in his book " De Sexu Plantarum," " On the Sexes of Plants," published in 1694, acknow- 

 ledges, " that he first became convinced of the truth of this doctrine bj perusing what had been written on this subject by Grew, and after- 

 wards by Ray, to whom he attributes the honour of establishing this important discovery." His experiments were only on the Maize, the 

 Mulberjy, the Ricinus, and the Mercwy, the three first of which he deprived of the stamen-bearing, or male flowers, and the last he 

 separated from its correspondent /e/naZe, and found that the seeds produced in each instance did not vegetate. 



f In 1703, Mr. Samuel Morland, desirous, as it should seem, of extending the Lewenhookian system of generation into the vegetable 

 kingdom, produced a paper before the Royal Society, in which he advances— that the farina is a congeries of plants, one of which'must be 

 conveyed through the style into every ovum, or seed, before it can become prolific. He founded his opinion " from observing an opening 

 in the arillus, or husk, of the bean, situate near where the plantule is found lodged, which he conceived was formed on purpose for the ad- 

 mission of a globule of the farina, which so disposed became the plantule." The refutation of this opinion will presently appear. 



In 1711, was read, " A Dissertation on the Structure and Use of the Parts of Flowers," by Mons. Geoffroy, before the Royal Aca- 

 demy of Science at Paris, where several curious remarks on the Farina, and some experiments on the Sexes of Plants, are given. 



Speakino- of the farina, Mons. Geoffroy says, " It would be ditficult to describe all the different figures of the farina; for however small, 

 each corpuscle has a regular, determinate, and constant figure. In the general run this figure is oval, with a groove the whole length, re- 

 sembling a grain of corn, or a seed of coffee, as in the Bryony, &c. But, 



1. In that of the St. John's Wort, Hypericum Yulgare, of Caspar Bauhine's Pinax. (Hypericum Perforatum, Lin.) appear like oval 



bodies, pointed at their extremities, and swelled in the middle. 



2. In that of the Trefoil, Melilotus officinarum Germanise, C. B. P. (Trifolium officinale, Lin.) like a cylinder, having a band running 



its length. 



3. That of the Yiolet, Viola Montana tricolor odoratissima, C. B. P. (Viola grandiflora, Lin.) presents a prism with four irregular sides, 



transparent, and reflecting different forms. 



4. That of the Borage, Borago floribus caeruleis, J. B. (Borago officinalis, Lin.) are likewise cylinders, but compressed in the middle, 



and shining in three different distinct spots. 



5. That of the Comfrey, Symphytum, Consolida major, C. B. P. (Symphytum officinale, Lin.) represents two crystal balls attached 



together. 



6. That of the Sycamore, Acer montanum candidum, C. B, P. (Acer Pseudo-Platanus, Lin.) presents a perfect cross. 



7. That of the Lily, Lilium album vulgare, J. B. (Lilium candidum, Lin.) an oblong oval, pointed at both ends, and with a groove its 



whole length. 



8. That of the Jonquil, Narcissus juncifolius, luteus, minor, C. B. P. (Narcissus Jonquilla, Lin.) have the form of a kidney. 



Q. That of the Spider-wort, Ephemerum Virginiacum, flore ccerules majori, J. R. H. (Tradescantia Virginica, Lin.) resembles a 

 barley-corn. 



10. That of the Euphorbia, Tethymalus Characias angustifolius, C. B. P. (Euphorbia Characias, Lin.) and of the Palm a Christi, Ricinus 

 Vulgaris, C. B. P. an ovoid figure, with a rising its whole length. 



11. That of the Acanthus, Acanthus rarioribus et brevioribus aculeis munitus, J. R. H. (Acanthus mollis, Lin.) 



12. That of the Spanish Broom, Genista Juncea, J. B. ^^Spartium junceum, Lin.) are oblong, rounded at their extremities, and has 



two bands, being two luminous eminences. 



13. That of the Tuberose, Hyacinthus Indicus, (Tuberosus, flore Hyacinth! orientalis, C. B. P. Polyanthes Tuberosa, Lin.) swelled in 



the middle, so as to make a prism with three sides. 



14. That of the Campanula Campanula pyramidalis, altissima, J. R. H. are round transparent, with light eminences, and a luminous 

 point in the center. 



15. That of the Passion-flower, Granadilla Polyphyllos fructu ovato, J. R. H. (Passifloi-a coerulea, Lin.) are nearly round, with small 

 risings over the surface. 



16. That of the Pink, Caryophyllus sylvestris calidarum regionum, J. R. H. are round, the surface a regiflar mosaic. 



17. That of the Geranium, Geranium sanguineum maximo flore, C. B. P. round, with a kind of navel, as in the apple. 



18. That of the Pompion, Melepepo compressus, C. B. P. (Cucurbiia Melopepo, Lin.) are round, with short pointed eminences. 

 10. That of the Sun-flower, and Marsh Cakha, Caltha palustus, have the surface covered with hairs. 



20, That of the Althea riretescens (Lavatera Olbia, Lin.) and the Convolvulus purpureas, C. B. P. (Convolvulus hederacius, Lin.) have 

 the surface covered with very short eminences. 

 After many observations on the Sexes of Plants, he relates the following experiment. 



I raised several plants of Maize, or Turkey corn, which on the summit of its branch produces male, or stameniferous flowers, and the 

 fruit is enclosed in a leafy sheath. 



I removed the stamina with all the care imaginable, as soon as they shew^ed themselves, and before the pistilliferous flowers appeared. 

 Upon most of these plants so served, the spike, after growing to a certain size, dried up, and the grains were withered, or only a few 

 "•rains'' attained its proper size, and these, but thinly scattered along the rachis, which might probably arise from imperfect castration. 

 The same event occurred to him with the Dog's Mercury. 

 As to the manner of the embryo being conveyed into the seed, he accords entirely with Morland. He says, " that the best microscopes 

 can never discover the plantule, or embrio, in the early stage of the pistillum, nor even when more advanced, unless the farina has reached 

 the stigma of the pistillum." His words are, " En effet, si Ton examine dans les plantes legumineuses, le pistile, ou cette partie qui devient 

 la gousse, avant que la fleur soit encore eclose, et qu'apres I'avoir debarrassee des feiiilles et des etamines, on la regarde au Soleil avec un mi- 

 croscope, on y remarque tres aisement les petites vesicules vertes et transparentes qui doivent devenir les graines placees dans leur ordre naturel, 

 et dans lesquelles on ne distingue rien autre chose qne I'enveloppe ou I'ecorce de la graine. En continuant d'observ^er pendant plusieurs jours 

 de suite dans d'autres fleurs a mesure qu'elles avancent, on remarque que ces vesicules grossissent et se remplissent d'une liqueur claire dans 

 laquelle, lorsque les poussieres se sont repandiies et lorsque les feiiilles de la fleur sont tombees, on commence a appercevoir un petit point ou 



" It was a pity he had not tried the experiment of sowing these grains. 



d globule 



