. The structure and development of mosses and ferns (Archegoniatae). --sp. Fig. 177.—A, Osmunda cinnamomea, section of a recently fertilised archegonium,X4S0. A spermatozoid has penetrated the nucleus of the egg, and several arein the space above the egg. B, Onoclea sensibilis. Egg fourteen hours after thepenetration of the spermatozoid, which is still recognizable within the egg nucleus,X900. (B, after Shaw.) gonium opens, the egg is depressed above, and the nucleusflattened. As soon as the archegonium opens, and the dis-organised contents of the neck cells are expelled, the tggbecomes turgid
. The structure and development of mosses and ferns (Archegoniatae). --sp. Fig. 177.—A, Osmunda cinnamomea, section of a recently fertilised archegonium,X4S0. A spermatozoid has penetrated the nucleus of the egg, and several arein the space above the egg. B, Onoclea sensibilis. Egg fourteen hours after thepenetration of the spermatozoid, which is still recognizable within the egg nucleus,X900. (B, after Shaw.) gonium opens, the egg is depressed above, and the nucleusflattened. As soon as the archegonium opens, and the dis-organised contents of the neck cells are expelled, the tggbecomes turgid, and the depressed upper part forms the recep-tive spot. (Fig. 177.) The mucilaginous matter ejected from the archegoniumretards the movements of the spermatozoids, and detaches thevesicle. As the spermatozoid penetrates the neck, it becomesmuch stretched out, and forces its way through to the centralcavity of the archegonium, by a slow screw-like penetrated into the ventral cavity, the coils drawtogether again, and the movements are much more rapid.
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Keywords: ., bookauthorcampbelldouglashought, bookcentury1900, bookdecade1910
