162 
EOYAL HOETICULTFEAL SOCIETY. 
witn the pollen or semen o another species, the influence of the 
foreign pollen or semen on the offspring produced is very distinctly 
observable. But the cases where this influence has previously 
shown itself in the mother plant, in a change of form, colour, or 
size in the fruit produced, have been hitherto exceedingly rare. 
The few instances may be found collected in Gaertner* or Darwinf. 
Thus Mauz asserts that he observed diff'erent kinds of fruit on a 
pear-tree, of which a number of blossoms had been castrated, and, 
as he supposed, fertilized afterwards by neighbouring trees. 
Pavis maintained that the fruit of apples, melons J, and maize 
underwent alteration in form, colour, and special qualities when 
they were planted near other kinds. Bradley even says that he 
had seen an apple which was sweet on one side and sour on the 
other, and one half of which became soft when boiled, while the 
other remained hard. But these are only observations and not 
experimental results. Wiegmann first obtained the latter in peas. 
Gaertner tested experimentally many of the statements which we 
have quoted, and made experiments on other plants besides. He 
was only able, however, to confirm Wiegmann' s results to a certain 
extent. He is therefore disposed (and with much reason) to 
attribute the majority of such cases to variation in the individual ; 
he allows, however, as a rare exception, the possibility of change 
even in the mother plant itself Other observers (as, for example, 
Knight §, and recently Nageli||) deny even the possibility of such 
an iuflaence. 
More recently Darwin has again quoted cases % where, by 
crossing yellow and dark maize, cobs were produced which con- 
tained both yellow and dark grains. Hildebrand confirms 
these observations, and further cites the instance of an apple 
which bore traces in its marking of the influence of another sort. 
But whilst the question has been in these cases only a variation 
* Die Bastardzeugung, p. 73. 
t Animals and Plants under Domestication, i. 397. 
I [Livingstone states (and the instance has not, I think, been quoted) that in 
the ease of CitruUus vulgaris, Schrad., which varies with sweet and bitter fruit, 
" melons in a garden may be made bitter by a few bitter Kengwein the vicinity. 
The bees convey the pollen from one to the other " (Travels in S. Africa^ 
p. 49).— Tr.] 
§ Trans. R Hort. Soc. v. p. 67. 
II Sitzungsberichte d. bayerischen Akad., cited by Hildebrand. 
' ^ Savi, cited by Darwin, I c. p. 400. ^* Bot. Zeit. 1868, p. 325, t. 6. 
