. High school botanical note book [microform]. Botany; Botanique. mi. 54 MIXrTE STHrvTCiu:. ffis. Fii;. Ji;.; is a (liaj;r;uu .showing tlio stnicttire of llicso [luiMiliar iiKirklii};s. Wlicn (H'lls stand cml to eml, and thin spots avo luft iu tlio cross-iiaititioiis between tliein, are foinied. Hero, a-ain, the tliin spots finally disa|.]iear, thus prnc- tieally unilin,!,' adja.'ent cells. Fij;. SCT illustratps these cells. HtTo ])s reiirosents tlio slinmkeii (lifted off tho I'li-forated cross-iiartition at .vy<); .v/, a sieve-iilate on the side-wall. On tlic rig
. High school botanical note book [microform]. Botany; Botanique. mi. 54 MIXrTE STHrvTCiu:. ffis. Fii;. Ji;.; is a (liaj;r;uu .showing tlio stnicttire of llicso [luiMiliar iiKirklii};s. Wlicn (H'lls stand cml to eml, and thin spots avo luft iu tlio cross-iiaititioiis between tliein, are foinied. Hero, a-ain, the tliin spots finally disa|.]iear, thus prnc- tieally unilin,!,' adja.'ent cells. Fij;. SCT illustratps these cells. HtTo ])s reiirosents tlio slinmkeii (lifted off tho I'li-forated cross-iiartition at .vy<); .v/, a sieve-iilate on the side-wall. On tlic right is a view of the sieve- liko wall. It sometimes happens that tho thickening takes place throngii- oiit the len^tli of a cell but in its (ni</f<:s only. Cells of this kind, wliick aro often found immediately under the surface of the stem iu tlie higher plants, are called mil, n- c/ii/iita cells. Fi^-. :.';iS is a transverse section of a iietiole of a Bej,-onia le:if, showiuij cojlenchyrna cells; e is the epidermis, (li( chlorophyll granules. ]5esidos tlio markings on tiio inside, cells often show mark- ings on tho outside. The pollcu-grains of the ilallow, for instance, are seen under the microscojie to bo covered witli pointed projections. Other pollou-grains, also, ex- hiliit outside markings of different sort,s. 'i'lio thickening deposit may be so in some cases as to almost completely fill up tho cavity of the cell (Fig. 2(;!)). Tho shells of nuts and the tough coatings of seeds consist of cells of this kind; but even in these cases the wall nniy be seen to be traversed by slender pores or canals, either simple or branched, radiating from tho centre of tho cell. To these hardened cells tho name Krhriiuhyiiia is api)lied. The Contents of Cells, if you look at Fig. 252, or, better still, if you have the oiipoi- tunity of viewing a ^loss-leaf through a good microscope, you will see that in the protoiilasmic lining of tho cells there aro numerous greenish, rou
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1895
