+----------+------------------------------------------+ | | Present series. | | +--------+----------+-----------+----------+ |Selection.| Mean, | Mean, |Regression.| No. of | | |parents.|offspring.| |offspring.| +----------+--------+----------+-----------+----------+ | 1 | 2.50 | 2.06 | 0.44 | 34 | | 2 | 2.52 | 1.86 | .66 | 205 | | 3 | 2.27 | 2.06 | .21 | 119 | | 4 | 2.69 | 2.41 | .28 | 194 | | 5 | 2.77 | 2.32 | .45 | 97 | | 6 | 3.08 | 2.67 | .41 | 45 | +----------+--------+----------+-----------+----------+ +----------+------------------------------------------+ | | General (plus) series. | | +--------+----------+-----------+----------+ |Selection.| Mean, | Mean, |Regression.| No. of | | |parents.|offspring.| |offspring.| +----------+--------+----------+-----------+----------+ | 1 | 2.51 | 2.05 | 0.46 | 150 | | 2 | 2.52 | 1.92 | .60 | 471 | | 3 | 2.73 | 2.51 | .22 | 341 | | 4 | 3.09 | 2.73 | .36 | 444 | | 5 | 3.33 | 2.90 | .43 | 610 | | 6 | 3.52 | 3.11 | .41 | 861 | +----------+--------+----------+-----------+----------+ The parents chosen from among these offspring ranged in mean grade from +2.37 to +3.25, average +2.69. They produced 194 offspring of grade +0.50 or higher (F₆, Table 47), the range for the first time lying wholly in the plus direction. The mean grade of the offspring was +2.41, a regression of 0.28. The parents of the next generation (F₇, Table 48) range in mean grade from +2.62 to +3.37, their average being +2.80. Their 154 offspring range from +0.75 to +3.75, mean +2.46, a regression of 0.34. The parents of the last generation in this experiment (F₈, Table 49) were of mean grade +3.08. They produced 45 offspring of mean grade +2.67, a regression of 0.41. As a result of a single cross with a wild race followed by six successive selections, a narrow-striped or minus family has thus been converted into a wide-striped or plus family. Considering the smaller number of offspring from which selections could be made, progress was quite as rapid in this series as in the larger plus selection series. The regression is surprisingly similar, generation by generation, in the two series. (See Table B.) But it seems improbable that the closeness of the agreement has any significance. _This series has the theoretical advantage of being derived from a single individual of the minus selection series._ CROSSES OF THE PLUS RACE WITH THE MINUS RACE.