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 645 B O T ANY. their office is not to ripen the fruit, but folely to tial parts of flowers, thefe parts mu ft neceflarily be the that anfwer the important purpofe of impregnation. organs of generatisin” Iking thus far advanced, Linnaeus affirms, that the “ 4. Abfcijfio.—The argument here is precifely the anthtra are the tejies, and that the pollen performs the fame with the caftration of the antherae ; and the refuk office of the male femen. Thefe affirmations he attempts is likewife the fame, namely, the deftrudion of the fruit. to eftablifh by the following, arguments; the firft of “ Thefe arguments,” concludes Linnaeus, “ are fufficient to demonftrate, that the ftigma is the female which he terms “ i. Pracedentia.—The antherae, or vegetable teftes, organ of generation, or that organ which is luited always precede the fruit; and as foon as the antherae for the reception and conveyance of the ftmen to the come to maturity, which conftantly happens before the vegetable eggs. Hence, plants may be faid to be in maturity of the fruit, they continue to throw out their attu veneris, when the antherae, or tefticuli, fpread pollen as long as the flower lafts; but decay and fall off their pollen over the ftigma or female vulva ’' To fhow how the coitus of vegetables is effected, is whenever the fruit comes to perfection. “ 2. Situs.—The antherae of all plants are uniformly our author’s next objeCt of inveftigation. He affirms, fituate in fuch a manner that the pollen may with the that the pollen is conveyed, by means of the wind or ingreateft facility fall upon the ftigma or female organ. feCts, to the moift ftigma, where it remains until it dif“ 3. Tempus.—The antherae and ftigmata always charges a fubtile fluid, which, being abforbed by the flourifh at the fame time, whether the flowers be of the veffels of the ftigma, is carried to the feeds or ova, and hermaphrodite or dioicous kind. impregnates them. His proofs are taken from the fol“ 4. Localumenta.—When the antherae are difleCted, lowing particulars. they difcover as great a variety of ftrufture as the peri “ 1. Ocnlus.—When the flowers are in full blow, carpia or feed capfules: For fome of them have one cell, and the pollen flying about, every one may then fee the as the mercury; fome two, as the hellebore, pollen adhering to the ftigma. This_ he illuftrates by “ 5. Cdftratio.—If all the antherae be cut off from mentioning as examples the viola tricolor, iris, campaan hermaphrodite plant, juft before the flowers begin to nula, fcc. expand, takifig care at the fame time that no plant of the “ 2. Proportio. — The ftamina and piftilla, in moft fame fpecies grows near it, the fruit will either prove en- plants are of equal heights, that the pollen, by the intertirely abortive, or produce barren feeds. ' vention of the wind,. may, with the greater facility, fall “ 6. Figura.—When the pollen of different plants ftigma. is examined by the microfcope, it exhibits as great a upon“ 3.theLocus.—The of moft plants furround variety of figures as is difcoverable in the feeds tbem- the piftillum, to give theftamina pollen ^n opportunity of falling felves on the ftigma at every breeze of wind. Even in the mo“ The accumulated force of thefe arguments”, conclafs, the male flowers ftand generally above the cludes Linnaeus, “ amounts to a full demonftration that the noecia female ones, to afford an eafier conveyance of the polantherae are the teftes, and that the pollen is the femen len to the ftigma. or gemtura of vegetables. “ 4. Tempus It is remarkable that the ftamina and “ The male organ being thus inveftigated, we hope,” piftilla conftantly appear at the fame time, even in plants fays Linnaeus, “ that none will hefitate to pronounce to the monoecia clafs. the ftigma to be the female organ, efpecially when the belonging “ 5 Pluvial.—The flowers of moft plants expand by following obfervations are fufficitntly attended to. the heat of the fun, and ffiut themfelves up in the evenT he piftillum is compofed of the germen, ftylus, ing or in rainy weather. The final caufe of this muft and“ ftigma The germen being only a kind of rudiment to keep the moifture from the pollen, left it fiiould of the future foetus or feed, ceafes to exift as foon as be, coagulated, and of courfe prevented from bethe flower comes to maturity. Neither is the, ftylus an being thereby blown upon the ftigma. effential part, as many flowers have no ftylus. But no “ 6. Patmicolee.—That the cultivators of palm trees fruit ever comes to maturity without the afliftance of the in ufe to pull off the fpadices from the males, and ftigma. It follows, that the ftigma muft be the female were fufpend them over the fpathse the females, is aoefted organ adapted by nature for the reception of the pollen by Theophraftus, Pliny, Profperof Alpinus, Kempfer, and or impregnating fubftance. This will appear ftill clear- many others. If this operation happened to be neglecter from the following chain of reafoning. ed, the dates were four and deftitute of nuts. Kemp1 • Situs.—The ftigmata alwaysthem. fituateBefides, fo that fer adds this Angular circumftance, that the male fpathe“pollen may with moft eafe fallare upon being thoroughly dried and kept till next feait is remarkable, that in moft plants (though not in all) dix, afterretained its impregnating virtue. the number of the ftigmata exaCtly correiponds with the fon,-“ ftill 7. Flores nutaiites.—As the pollen is fpecifically loculamenta or cells of the pericarpuim. heavier than air, fuch flowers as have their piftillum 2. Tempus.—Here the obfervation, that time, the ftigmata than the ftamina, hang down, or incline to one and“ antherae conftantly flourilh at the fame is re- longer fide, e. g. the fritillaria, campanula, &c. An eafy adpeated. niiinon of the pollen to the ftigma, is the final caufe of 3- Decidentia.—The like. this appearance. the“aqtheras, decay and fall ftigmata off as foonof asmofttheyplants, have dif%. Subrnerji.—Many plants that; grow below wacharged their proper function; which evidently ftiows, ter, emerge when their flowers begin to blow, and fwim Vol. I. Numb. 27 3 8A • upon