90 PRESENT-DAY GARDENING 
An interesting paper on this race of hybrids; by Pro- 
fessor Henslow, was published in the Jotirnal of the Royal 
Horticultural Society, vol. xiii. p. 240. The double-flowered 
varieties were obtained from a flower which possessed one 
or two petaloid stamens and was fertilised with its own 
pollen. From its seeds fifteen plants were raised, some of 
which had single flowers, others semi-double, and others 
quite double. 
The species not only readily intercross, but the hybrids 
obtained from them are perfectly fertile. The present race 
is the result of crossing and recrossing to the fourth genera- 
tion, so that there has been a thorough mixing of the 
characters of the several species used. Some interesting 
facts were elicited by these crossings. Thus, when a white 
flower was crossed with a yellow one, the progeny were 
either white or yellow, generally white. White crossed 
with orange sometimes yielded pink ; crimson crossed with 
yellow gave scarlet ; pink crossed with yellow gave pure 
yellow, except on the anthers, which were pink. As a rule, 
better forms of flowers and clearer colours are secured 
when hybrids are crossed with species than when hybrids 
are crossed with each other. 
