Text-book of botany, morphological and physiological . ils of the antherozoid, which islarger in this class than in all other Crypto-gams, bears an appendage on the inner sidewhich Hofmeister terms an undulating Float,Schacht a thin-walled vesicle of protoplasm, andwhich contain granules of starch and sap (com-pare with Ferns and Lycopodiaceoe). The Aichegonia are developed from singlecells of the anterior margin of the thick and fleshy lobes of the female prothallium. As the tissue of the prothallium be-neath them continues its growth, the archegonia come, as in Pellia, to standon its upper s
Text-book of botany, morphological and physiological . ils of the antherozoid, which islarger in this class than in all other Crypto-gams, bears an appendage on the inner sidewhich Hofmeister terms an undulating Float,Schacht a thin-walled vesicle of protoplasm, andwhich contain granules of starch and sap (com-pare with Ferns and Lycopodiaceoe). The Aichegonia are developed from singlecells of the anterior margin of the thick and fleshy lobes of the female prothallium. As the tissue of the prothallium be-neath them continues its growth, the archegonia come, as in Pellia, to standon its upper surface. The mother-cell of the archegonia, after it has becomemuch curved, divides by a wall parallel to the surface of the prothallium; thelower of the two daughter-cells, which is entirely sunk in the tissue of the pro-thallium, becomes the central cell; from the outer one is formed the neck, con-sisting, at a subsequent period, of four parallel rows of cells. The four uppercells become very long; the four middle ones remain shorter; the four lower. Pig. 269.—First stage of development of tlieprothallium of Eguiseium Telmateia; tu the firstroot-hair; / rudiment of the prothallium. Theorder of development follows the numbers I—lI{X about 200). 3^4 VASCULAR CRYPTOGAMS. ones scarcely elongate at all, and contribute, by their multiplication, like the cells ofthe prothallium which surround the central cell, to the formation of the wall of theventral part of the archegonium, which consists of one or two layers. The oosphereis produced in the central cell, the contents of which it gradually displaces. Thefour upper long cells of the neck curve radially outwards, when the canal of theneck is being formed, like a four-armed anchor \ Immediately after fertilisationthe canal of the neck closes, the oosphere, the nucleus of which disappears (and
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
