The Origin of Linaria Vulgaris Peloria. 201 
preferably after castration. The seeds collected after 
this operation are said to give from 25 to 40 % double 
plants the number varying directly with the care with 
which the castration was carried out. 
Double flowers are also subject to sectorial and bud- 
variation. A chestnut tree (Acsculits Hippocastaniun] 
at Geneva, a single branch of which has borne double 
flowers for many years, 1 is perhaps the best known ex- 
ample of the latter, whilst our Fig. 37 gives an interest- 
ing case of the former. It is a flower of the pure white 
Anemone coronaria, ''The Bride," which, like the Py- 
rcthrum, I owe to the kindness of MR. KRELAGE. It grew 
in a bed of the single variety; the plant which bore it 
had exclusively single flowers with the exception of 
this one. On the one half there were stamens only, as 
is shown by the figure; in the other half, however, the 
vast majority of stamens were transformed into narrow 
petals, just as happens all round the stigma in the double 
form. The single variety frequently exhibits more or 
less definite traces of doubling, and from these MESSRS. 
KRELAGE have succeeded in producing a double sort and 
putting it on the market. But a sectorial variation like 
that figured has only been observed once in the course 
of many years. 
20. THE ORIGIN OF LINARIA VULGARIS PELORIA. 
About ten years after the appearance of the first 
edition of DARWIN'S Origin of Species (1859) HOF- 
1 A. P. DE CANDOLLE, Physiologie vegetale, 1832, II, p. 479, and 
ALPH. DE CANDOLLE, Geographic botanique, 1855, H> P- 1080. This 
tree stood in the garden of M. SALADIN DE BUDE near Geneva. Many 
cuttings made from the double-flowered branch have been distrib- 
uted. 
