32 BOOK OF THE SCENTED GARDEN 
LEAF Opours Versus FLoRAL Opours 
When we compare leaf odours with flower odours we 
find a considerable difference between them. ‘Thus in 
the case of the orange there is a difference between the 
essential oils of the flowers and of the Jeaves, and of that 
of the rind of the fruit, which afford three different 
kinds of perfume. 
Then floral odours are generally positive, being exhaled 
by most flowers spontaneously as it were, so that you 
must inhale floral odours whether you like them or not. 
Leaf odours, on the other hand, are latent or negative, 
and are rarely to be detected except after the leaves have 
been touched, pressed, or bruised. Both leaf and flower 
perfume depends on the same essential oil being in 
differeut states or conditions. 
Floral odours again are emitted only at particular 
times, that is to say, just when the andrcecial whorl 
attains maturity, and the flowers are quite fresh; and 
even then, in the case of many Orchids and other flowers, 
their scent is intermittent, and only to be perceived at 
different times of the day or night—this time, as we 
suppose, having some connection with the diurnal or 
nocturnal visits of the insects that act as marriage priests 
in their native wilds. But, onthe other hand, leaf odours 
are persistent—‘‘ready if sought” seems to be their 
motto—and not only are scented leaves fragrant when 
green and fresh, but often retain their perfume long after 
they are yellow or brown and sere. Mr Hudson, of 
Gunnersbury, to whom I am indebted for a collection of 
scented Pelargonia, tells me that the old yellow or brown 
leaves of these charming plants are sweeter even than the 
fresh ones. ‘This is doubtless owing to the water of the 
leaves having evaporated, thus leaving behind the essential 
oils in a more concentrated form. This permanency of 
odour is a strong recommendation, and no greenhouse or 
