318 Xiitrition and Selection. 
of the perumbellate inflorescences appeared in July. Be- 
fore July there were 21%, in July 47%, in August 38%, 
and this last record was made on over 500 inflorescences. 
I continued the experiment by planting out some of the 
creeping stems of this plant into two other beds, of which 
one consisted of good garden soil, the other of dry sandy 
soil. In this year under less favorable conditions of 
growth, the proportion of anomalies was less . Amongst 
about 300 inflorescences in each bed 6% had elongated 
on the sand bed and 12% on the control bed. On the 
former the plants were small, their leaves being smaller, 
and paler and less numerous than the normal. 
This experiment shows that the proportion of anom- 
alous inflorescences is to a very large extent determined 
by external conditions even when the method of propa- 
gation is purely vegetative. 
In the literature of this subject we sometimes come 
across the view that anomalies are favored by improved 
external conditions because more nutriment is necessary 
for their development, and the fasciations, and the multi- 
plication of the number of leaves, leaflets, etc., are given 
as instances. As a matter of fact even when the anom- 
aly consists in a reduction of parts the same relation ob- 
tains. This is shown by the second instance that I shall 
give. This is Potentilla anserina, of which I found some 
plants with occasional tetramerous flowers near Hilver- 
sum in 1889 among the ordinary pentamerous ones. I 
planted them out and divided them, and in the summer of 
1891 I selected the best specimens and made sure that 
all the runners were still organically connected. In 1892 
I planted out one-half of this on a manured bed and the 
other half on an unmanured bed adjacent to it. 
From the middle of July to the beginning of August, 
