Page:Encyclopædia Britannica, first edition - Volume I, A-B.pdf/765

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.
XXX (643) XXX

B O T The Root a, is of the branchy kind, and perennial. The Leaves of (which b in the plate is an outline) are about fixteen in number, grow near the root, about two feet long, and are furnifhed with petioli or foot-ftalks. —The petioli are about a foot long, cylindrical, plane above, fmooth, of a green colour, but in fome places interfperfed with fmall, narrow, purple fpots ; at the bafe of the leaf, the petiolus terminates in three or five large nerves or ribs, which are prominent above; the leaves are ovated, deep cut, with lharp lacinia or fegments ; the fuperior part of the bafe is green, the inferior of a whitilh green, and both are alit-le rough. The Caulis or Stem is eredt, fomewhat cylindrical, fiftulous or hollow within, jointed, (heathed, rough, ftriated, about eight feet high, and about two inches over near the bale. It has fourteen joints, each of which, from the bafe to the ninth joint, is furnilhed with a refledted leaf, placed alternately, gradually diminilhing as they rife higher, and the petiolus forms a kind of fheath, which embraces the ftem. The Pedunculi or Foot-stalks of the flowers, which are numerous, arife from the alas or arm-pits of the leaves, are almofl eredt, unequal, ftriated, cylindrical, plainilh at the bafe, and out of their fides other

A N Y. 64} foot-flalks arife, to be diflributed in the fame manner, c, is a flowering branch feparated from the flem. The Taste, Odour, and Colour of the Root are precifely the fame w ith thofe of the foreign rhubarb. The Taste of the Flowers is aflringent, herbaceous and fubacid ; they have no fenfible fmeli. The Taste of the Leaves is bitterifh, aftringent, and herbaceous; the tafle of the Ribs or Nerves is acid, bitterilh, and very ungrateful;;—the tafie of the Stem is a little four. We have now pretty fully explained the method of reducing plants to clafl’e?, orders, genera, and fpecies, according to the fexual fyftem of Linnaeus. The manner in which this explanation has been executed was fuggefted by the difficulties which naturally occur to a perfon unacquainted both with the fubjedt and the fyllem. Although this manner has not, fo far as we know, been hitherto attempted, we hope it will not be the lefe acceptable to the public, efpecially as it is likely to be more ufeful to the botanical ftudent. It only now remains to make the reader more fully acquainted with the origin and nature of the fexaal fyftem.

S ErC T. III. Of the S EXES of PLANTS. A S many philofophers and botanifb deny that fuch a lity of the ftamina and ftyli of plants. The refult of thing as the dilfindHon of fexes takes place in vege- this converfation was the mutual agreement of thefe two tables, it will be neceflary to give a narration of the ar- eminent naturalifts, that the ftamina and ftyli of vegeguments employed by Loth parties on this fubjedt. We tables were analogous to the organs of generation in anifhall begin with the arguments in favour of- the fexes. mals,-and that they were adapted by nature to anfwer purpofes. Dr Grew, in his anatomy of plant?, Linnaeus, like every perfon attached to* a parti- the fame enumerating the analogies between plants and anicular dodtrine or theory, is at great pains in tracing after mals, concludes, that the pollen probably emits certain the notion of fexes in plants to the remoteft periods of vivific effluvia, which may ferve for the impregnation of antiquity. He informs us, that Empedocles, Anaxago- the feeds. ras, and other ancient philofophers, not only attributed Mr Ray gave a further fandtion to the dodtrine of the diftindUon of fexes to plants, but maintained that fexes, by concurring with Grew, and adding fome furthey were capable of perceiving pleafure and pain. from analogy. Hippocrates and Theophraftus are next introduced as therIn illuftrations the-year 1695, Camerarius attempted to prove the diftinguilhing the conyza, the abies, the filix, &c ‘. into fexes of plants. But, as he trufted folely to the palmmale and female. The latter of thefe writers affirms, tree, and withal feemed to be doubtful as to the authenthat the fruit of the female palm will not germinate un- ticity of the fadt, he cannot be confidered as having done, lefs the pollen of the male be fhaked over the fpatha of any thing in confirmation of -the fexual hypothefis. the female, previous to the ripening of the feed Mr Morland, in the year adopted the fame hyDiofcorides takes notice of a male and female mandra- pothefis; but gave it a new1703, modification, by fuppofing gora, mercurialis, ciftus, 6r., that the pollen contained the feminal plant in miniature; Pliny does not confine his views of fex to animals, but confequently, that one pollen at leaft behoved to be exclaims, that every thing this earth produces is charac- and conveyed into every feparate feed before it could be proterized by the diftindtion of fex. perly impregnated. Analogy and the ftrudture of the. From the days of Pliny to thofe of Caifalpinus, who are the only arguments he employs. lived in the i6th century, the analogy between the vege- partsSome years after this, Mr GeofFroy wrote a treatife table and animal feems to have been entirely negledted. fexes of plants : But as he advanced nothing new, Cxfalpinus tells us, that the males of the oxycedrus, on the fliall take no further notice of him. taxus, mercurialis, urtica, and cannabis, are barren; weVaill.tnt, in the 1717, judicioufly confidering that and that the females of thefe plants only bear fruit. CHtial in the ftylu's of moft plants was too narrow After Casfalpinus, we find Dr Grew and Sir Thomas the to admit the pollen republifhed Dr Grew’s theory Millington engaged in a converfation concerning the uti- of impregnation by itfelf, means of a fubtile feminal aura. Thefe