The American botanist and florist; including lessons in the structure, life, and growth of plants; together with a simple analytical flora, descriptive of the native and cultivated plants growing in the Atlantic division of the American union . s pass by absorption into the sac. 451. This is the view of Mohl, Henfrey, and of botanists generally. But Schleidenmaintains that the end of the pollen-tube actually penetrates the sac, and itself becomesthe embryonic cell. The pollen-grain is in this view the primitive cell, and is itself quick-ened into development by the contents of the embryo sac (
The American botanist and florist; including lessons in the structure, life, and growth of plants; together with a simple analytical flora, descriptive of the native and cultivated plants growing in the Atlantic division of the American union . s pass by absorption into the sac. 451. This is the view of Mohl, Henfrey, and of botanists generally. But Schleidenmaintains that the end of the pollen-tube actually penetrates the sac, and itself becomesthe embryonic cell. The pollen-grain is in this view the primitive cell, and is itself quick-ened into development by the contents of the embryo sac (522). 452. However this mary be, the embryonic globule, thus some- lU PHYSIOLOGICAL BOTANY. how endoAved with a new instinct, immediately becomes a newcentre of growth. First it expands to a proper cell, attached tothe Avail of the sac near the microj^yle. It then, by division andsubdivision, multiplies itself, and begins totake form according to the species, showingcotyledon, plumule, etc., until fully devel-oped into the embryo (523). 453. In the case of the Coniteks (Pines, Cedars, Firs),where no styles or stigmas exist, the pollen falls directly intothe micropyle of the nakedovule, and its tubes settle intothe tissue of the
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1870
