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This eBook from the Gutenberg Project consists of approximately 459 pages of information about Effects of Cross and Self Fertilisation in the Vegetable Kingdom.

In Table 7/B the relative weights of the crossed and self-fertilised plants, after they had flowered and had been cut down, are given in the few cases in which they were ascertained.  The results are, I think, more striking and of greater value as evidence of constitutional vigour than those deduced from the relative heights of the plants.

The most important table is Table 7/C, as it includes the relative heights, weights, and fertility of plants raised from parents crossed by a fresh stock (that is, by non-related plants grown under different conditions), or by a distinct sub-variety, in comparison with self-fertilised plants, or in a few cases with plants of the same old stock intercrossed during several generations.  The relative fertility of the plants in this and the other tables will be more fully considered in a future chapter.

Table 7/A.  Relative heights of plants from parents crossed with pollen from other plants of the same stock, and self-fertilised.

Heights of plants measured in inches.

Column 1:  Name of Plant.

Column 2:  Number of Crossed Plants measured.

Column 3:  Average Height of Crossed Plants.

Column 4:  Number of Self-fertilised Plants measured.

Column 5:  Average Height of Self-fertilised Plants.

Column 6:  x, where the ratio of the Average Height of the Crossed to the
Self-fertilised Plants is expressed as 100 to x.

Ipomoea purpurea—­first generation: 
  6 :  86.00 :  6 :  65.66 :  76.

Ipomoea purpurea—­second generation: 
  6 :  84.16 :  6 :  66.33 :  79.

Ipomoea purpurea—­third generation: 
  6 :  77.41 :  6 :  52.83 :  68.

Ipomoea purpurea—­fourth generation: 
  7 :  69.78 :  7 :  60.14 :  86.

Ipomoea purpurea—­fifth generation: 
  6 :  82.54 :  6 :  62.33 :  75.

Ipomoea purpurea—­sixth generation: 
  6 :  87.50 :  6 :  63.16 :  72.

Ipomoea purpurea—­seventh generation: 
  9 :  83.94 :  9 :  68.25 :  81.

Ipomoea purpurea—­eighth generation: 
  8 :  113.25 :  8 :  96.65 :  85.

Ipomoea purpurea—­ninth generation:  14 :  81.39 :  14 :  64.07 :  79.

Ipomoea purpurea—­tenth generation: 
  5 :  93.70 :  5 :  50.40 :  54.

Ipomoea purpurea—­Number and average height of all the plants of the ten
generations:  73 :  85.84 :  73 :  66.02 :  77.

Mimulus luteus—­three first generations, before the new and taller
self-fertilised variety appeared:  10 :  8.19 :  10 :  5.29 :  65.

Digitalis purpurea:  16 :  51.33 :  8 :  35.87 :  70.

Calceolaria—­(common greenhouse variety): 
  1 :  19.50 :  1 :  15.00 :  77.

Linaria vulgaris: 
  3 :  7.08 :  3 :  5.75 :  81.

Verbascum thapsus: 
  6 :  65.34 :  6 :  56.50 :  86.

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