388 GENETICS IN RELATION TO AGRICULTURE 
It consisted of absence of yellow and decrease of red in the younger 
leaves of afew plants. Six of the 15 patterns that arose as bud mutations 
also appeared more or less frequently as fluctuating variations on certain 
plants. The derivations of the various color patterns are shown by the 
diagram in Fig. 160. It will be noted that the original pattern, No. 2, 
is described as green-yellow-red blotched which means green center, 
yellow marginal border and red blotches on the epidermis. In the same 
way the description of pattern No. 4 is interpreted as green center, yellow- 
spotted marginal border and red blotches on epidermis. 
The frequency with which these various bud mutations occurred is 
shown in Table LIV. Here are indicated under ‘‘ Plants”? the number 
of plants in which each type of change might have occurred, under 
“Frequency,” the actual number of bud mutations that did appear, and, 
finally, the ratio of bud mutations to constant buds. This ratio is 
obtained by assuming that on the average each plant produced 200 buds. 
Taste LIV.—FRequency or Bup Mutations Propucine New Couor Patrerns 
AND Lwar-sHAPEs IN Conus. (After Stout.) 
Type of change | Plants) Frequency | Ratio 
Increase of yellow and decrease of green............ | 827 | 27 1: 6,130 
Decrease of yellow and increase of green............| 740 50 1: 2,960 
Reversal of positions of green and yellow........... | 450 8 1:11,250 
Increase of epidermal red to solid red.............. 770 8 1: 19,250 
Decrease of epidermal red, complete loss.......... | 815 19 1: 8,580 
Decrease of epidermal red, all cases................ | 815 21 1: 7,760 
Appearance of the laciniate character ......... ia | 765 13 1:11,770 
Entire leaf from laciniate leaf..................006: | 68 1 1: 13,600 
Stout remarks that these data indicate the tendencies of the bud 
variations and give a clew to the behavior of the characters in question. 
Thus, decrease of yellow occurred twice as often as increase of yellow, 
and loss of red 2.2 times as often as increase of red. Although these 
data indicate a tendency toward loss rather than gain of the two colors, 
the fact that the number of mutations involving gain is about half as 
large as the number involving loss has considerable interest. It has been 
generally considered that mutations involving addition of a character are 
exceedingly rare. While this may be the case in many pure species, it 
would appear from the above evidence that among the progeny of species 
hybrids such mutations may be relatively frequent. 
The manner of appearance of these bud mutations was typical of 
somatic factor mutations. Stout says, for example, ‘the loss of yellow, 
loss of green, and gain and loss of red all occurred in single branches and 
in sections of branches. Frequently two quite different changes occurred 
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