Elementary studies in insect life Elementary studies in insect life elementarystudie00hunt Year: 1902 PLANTS AND INSECTS FIG. 75. Flower of Bartlett pear—natural size. (After Waite.) pollen escapes from the anthers of the same flower. The stigma often extends through the petals before they are fully open, thus offering the possibility of pollination from some earlier blossoming variety, - another way for cross-fertili- zation to occur. The process of fecundation Waite describes : ' Soon after its protrusion the stigma se- cretes a sugary fluid, often in sufficient quantity to be quite perc
Elementary studies in insect life Elementary studies in insect life elementarystudie00hunt Year: 1902 PLANTS AND INSECTS FIG. 75. Flower of Bartlett pear—natural size. (After Waite.) pollen escapes from the anthers of the same flower. The stigma often extends through the petals before they are fully open, thus offering the possibility of pollination from some earlier blossoming variety, - another way for cross-fertili- zation to occur. The process of fecundation Waite describes : ' Soon after its protrusion the stigma se- cretes a sugary fluid, often in sufficient quantity to be quite perceptible. In this the pollen grain readily germinates and throws out a slender, thread-like tube, which grows downward into the pistil and through specially soft tissue, adapted to its growth, until it reaches the ovules. Here it enters an opening in the two outer coats of the ovule and conies in contact with the germ-cell, or egg- cell. A number of inter- esting and complicated changes now take natural size, in the protoplasm of this cell and in the end of the pollen tube. A part of the con- tents of the latter actually passes through the cell-walls into the egg-cell, which, un- der this stimulus, immediately begins to showing only the T< ,w and divide, ultimately developing five pistils—nat- '. into the germ of the seed. This stim-
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