252 
Non-Isolable Races. 
generation there were no flowers with more than 14 
o 
petals. Now there are 38, distributed as follows : 
Petals 15 16 17 18 19 20 21 22 23 31 
Number of flowers 18 852111011 
It should be noted, however, that they were found 
amongst a group of 4425, and therefore only amount to 
about \% (0.86%). But as not a single one was found 
in 1891 amongst 243 flowers, a genuine, although only 
a slight, advance has taken place. 
The great majority of the 295 plants which were 
flowering in August and formed the 1892 culture, had 
F. 
Fg. 52. Ranunculus bulbosus semiplenus. Composition of 
the fifth generation in 1892. A, the curve of some "ata- 
vists" ; M, the curve of intermediate individuals ; V, the 
group of extreme variants. The figures refer to the 
number of petals per flower. 
individual curves whose maximum was at 9. But amongst 
their number were variants and extreme variants also. 
On the one hand there were "atavists" with a maximum 
on the ordinate of five petals, i. e,, with a one-sided curve, 
as in those from the original locality ; on the other hand 
there were variants on the plus side which bore on the 
average eleven petals per flower. In one case even a mean 
of 13 petals was reached. These curves were two-sided, 
and not, as in the five-leaved race of the red clover, in- 
