Page:Popular Science Monthly Volume 85.djvu/331

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PHENOMENA OF INHERITANCE
327

1. Results of Crossing Individuals with one Contrasting Character.—Having determined that these characters were constant for certain varieties or species Mendel then proceeded to cross one variety with another, by carefully removing the unripe stamens, with their pollen, from the flowers of one variety and dusting upon the stigma of such flowers the pollen of a different variety. In this way he crossed varieties

Fig. 50. Diagram Showing the Results of Crossing Yellow-seeded (Lighter Colored) and Green-seeded (Darker Colored) Peas. From Morgan after Thompson.)

of peas which differed from each other in some one of the characters mentioned above, and then studied the offspring of several successive generations with respect to this character.

In every case he discovered that the plants that developed from such a cross showed only one of the two contrasting characters of the parent plants, i. e., all were round-seeded, yellow seeded, tall, etc., although one of the parents had wrinkled seeds, green seeds, or short stem, etc.

Those characters which are transmitted entire or almost unchanged in the hybridization are termed dominant and those which become latent in the process, recessive.