. Domesticated animals and plants : a brief treatise upon the origin and development of domesticated races, with special reference to the methods of improvement . Breeding; Domestic animals; Plants, Cultivated. HOW CHARACTERS ARE TRANSMITTED 123 in good time develop into a single kernel of corn ; but if all does not go well, the silk will grow longer for a time, and final])- wither away, but the kernel will not develop, and nothing but a bare cob will be found at husking time. What is it that deeides whether there is to be or is not to be a kernel ? The answer to that question involves the who
. Domesticated animals and plants : a brief treatise upon the origin and development of domesticated races, with special reference to the methods of improvement . Breeding; Domestic animals; Plants, Cultivated. HOW CHARACTERS ARE TRANSMITTED 123 in good time develop into a single kernel of corn ; but if all does not go well, the silk will grow longer for a time, and final])- wither away, but the kernel will not develop, and nothing but a bare cob will be found at husking time. What is it that deeides whether there is to be or is not to be a kernel ? The answer to that question involves the whole machinery of transmission. Every farmer boy knows that at the top of the stalk is the tassel, and that this tassel has the habit at times of shedding large amounts of yellow powder, particu- larly after a rain or in the still hours of the early morn- ing after a warm but quiet night. Most farmer boys know that in some way this golden-yellow dust, or "pol- len," is connected with the crop, but few of them know in just what way. If we use a microscope to magnify size, and see exactly what is involved and what is going on, it would be somewhat as follows : First of all, the silk would be found to be soft and pulpy throughout its entire length, somewhat "sticky" and branched at the top or outer end, and connected at the base with a single cell, called an ovule.^ Now this ovule is the important part, for it is what develops into the kernel of corn if all goes Fig. 18. Ear covered for ten days with a paper sack preventing fertilization. The silk remained fresh and continued to grow. It has been known to reach a length of two feet while awaiting the pollen 1 A "' cell " is the structural unit of the plant or animal. As a building is made of bricks, so the plant or animal body is made up of cells or sacks filled with a semifluid matter known as protoplasm, which is a kind of general name for the material of different parts of the body; that is t
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