12 
enne at all. It is considered a degenerate type, 
because of its small, worthless fruit and weak- 
ly growing plant. It probably could not sur- 
vive in field competition with normal plants. 
Driver’s Dwarf (Fig. 6) has a diminutive 
form of plant and fruit, combined with collar 
of slips and an intensified purple anthocyanin 
pigment in the leaves. This may represent a 
change from the normal slip type of the Cay- 
enne variety to the collar-of-slip strain. On the 
other hand, the mutation giving rise to dwarf 
and increased anthocyanin may have occurred 
in a collar-of-slip strain plant which was al- 
ready in the field population. The dwarfing 
and anthocyanin intensification appear to 
have been simultaneous changes. 
Fig. 6. A normal Cayenne fruit on the left, with a 
fruit of the mutant Driver’s Dwarf on the right. 
Discussion of these more obvious mutant 
types naturally leads to the question of the 
possible occurrence of other mutations which 
are less conspicuous and less easily measured. 
Undoubtedly mutations of this kind take 
place, but the demonstration of the existence 
of mutations of slight phenotypic effect is 
much more difficult, because of overlapping 
variations of a non-hereditary nature. 
Some examples of these small or elusive 
mutant effects are briefly described to show 
that at least a few are present in the variety. 
PACIFIC SCIENCE, Vol. V, January, 1951 
Two Cayenne clones were found to show 
a slightly darker green color, which could be 
recognized easily when a fairly large group of 
these were growing adjacent to a group of the 
normal variety. A clone may be thought of as 
one plant multiplied many times by vegeta- 
tive reproduction, and all plants of a clone 
have identical heredity. Chemical analyses of 
leaves revealed a higher chlorophyll content 
in these darker green leaves. A mutation of 
slight effect on chlorophyll production was 
probably the origin of these darker green 
clones. 
The elongated fruit mutation listed in 
Table 1 develops a large number of multiple 
crowns and fasciated fruits when grown in 
warm, dry areas, but only normal plants ap- 
pear in the cool, more moist areas. In this 
case the additional character of multiple 
crowns is quite obvious under one environ- 
mental condition and disappears (or merges 
into the normal pattern) when grown under 
other conditions. 
The number of slips produced per plant is 
a character subject to considerable variation 
due to differences in the environment during 
the growth period. This is well illustrated by 
the effect of relative crowding of plants in the 
field. Close planting reduces the number of 
slips, and, conversely, widely spaced plants 
permit a larger number of slips to develop. 
Table 3 shows the variation in number of slips 
resulting from an experimental planting of 
Cayenne with 10, 12, 14, and 16 inches be- 
tween plants (that is, with different degrees of 
crowding) . 
TABLE 3 
Effect of Different Plant Spacings on Slip 
Production 
PLANT SPACING AVERAGE NUMBER 
IN INCHES OF SLIPS 
10 2.51 
12 3.33 
14 3.95 
16 4.36 
Odds — 19 to 1 0.43 
Odds — 99 to 1 0.60 
Because of the susceptibility of this char- 
acter to variation due to environmental dif- 
