The microscope and its revelations . ulbels/ from their analogy to the bulbels or detached buds ofFig. 130. Elowering Plants) are ^ at first evolved as single globular cells, sup-ported upon other cellswliich form their foot-stalks; these siugle cellsgradually undergo mul-tiplication by duplica-tive subdivision, untilthey evolve themselvesinto the disks; andthese disks, when ma-ture, spontaneously de-tach themselves fromtheir footstalks, and liefree within the cavity ofthe conceptacle. Mostcommonly they are atlast washed-out by rain,and are thus carried todifferent parts of theneighboming soil
The microscope and its revelations . ulbels/ from their analogy to the bulbels or detached buds ofFig. 130. Elowering Plants) are ^ at first evolved as single globular cells, sup-ported upon other cellswliich form their foot-stalks; these siugle cellsgradually undergo mul-tiplication by duplica-tive subdivision, untilthey evolve themselvesinto the disks; andthese disks, when ma-ture, spontaneously de-tach themselves fromtheir footstalks, and liefree within the cavity ofthe conceptacle. Mostcommonly they are atlast washed-out by rain,and are thus carried todifferent parts of theneighboming soil, onwhich they grow veryrapidly when well sup-plied with moisture;sometimes, however,they may be foundgrowing whilst still con-tained within the con-ceptacles, forming na-tuial grafts (so tospeak) upon the stockfrom which they havebeen developed and de-tached; and many ofthe irregular lobes which the frond of the Marchantia putsforth, seem to have this origin.—When this plant vegetatessituations, which are favourable to the nutri-. Gemmiparous coneeptacles of Marchcmiiapolymorpha:—A, conceptacle fuUy expanded,rising from the surface of the frond a a, andcontaining disks abeady detached;—b, firstappearance of conceptacle on the surface ofthe frond, showing the formation of its fringeby the splitting of the cuticle. { tive processes, it does not readily produce the true fructifica-tion, which is to be looked-for rather iu plants growiug in GEifERATIVE APPAILATUS OF MAECHA^TIA, 391 Fi&. 131. more exposed places. Eacli of the stalked peltate (sliield-like) disks contains a number of flask-skaped cavities openingupon its upper surface, which are brought into view by avertical section; and in each of these cavities is lodged an antheridium/ composed of a mass of sperm-ceUs/ withinwhich are developed antherozoids like those of Chara (§ 202),surmounted by a long neck that projects through the mouthof the ilask-shaped cavity. The wheel-like receptacles(Fig. 128) on the other hand
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Keywords: ., bookcentury1800, booksubjectmicroscopes, booksubjectmicroscopy
