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colour of flowers. To refer to our practical experience in such 
matters, is it not generally true that a dry warm season, with plenty 
of sunlight and clear blue sky, is accompanied by a more brilliant 
colour in our flowers, and that the latter are also more abundant. 
Owing to the effect of these conditions, the seed is more plentiful ; 
while under the contrary conditions, the reverse is generally the case. 
It is true that the deeper colour generally accompanying a mountain 
Flora may seem an exception to this, but it should be remembered 
that here we generally have the presence to a certain extent, 
especially on the lower slopes of the mountains, of more tropical 
conditions as regards a greater amount of moisture. Coming now 
to foliage, I think we shall find that the conditions above-named as 
probably affecting the colour of flowers have here also a propor- 
tionate effect, for the foliage of tropical climates is generally of a 
deeper colour than that of temperate regions, that of the latter 
being of lighter hue; and, indeed, the further north we go within 
the temperate zone, the more, as a general rule, do we find this to 
be the case, the comparatively greater amount of light rays being 
accompanied by a correspondingly lighter colour of the leaves. 
There is, however, one exception to this, and so far, as I know, but 
one—that of New Zealand, where the foliage is of a lighter colour, 
more approaching that of our own vegetation ; but the climate of 
New Zealand is one nearly similar to our own in character, in the 
free access and circulation of air admitting more readily the rays of 
light ; and while it naturally increases the extent of evaporation, it 
also tends to check the superabundant presence of that moisture, 
which, as arule in tropical climates, owing to the denser character of 
the foliage, which also helps to produce it, tends to perpetuate the 
condition of things which we find there—the prevalence of a deeper 
hue in the foliage. Again, it is, I believe, a fact that dull-coloured 
flowers generally have the sweetest scent ; while bright and brilliant- 
coloured ones have either no scent at all, or a disagreeable one. In 
our own country, for instance, we find that those of brilliant colour, 
which are perhaps predominant, are comparatively scentless, and 
that this rule is generally borne out among wild flowers. I think 
_ the cultivated flowers are scarcely a fair test, as the colour, and 
perhaps scent, too, can be modified to almost any extent. There 
ave, doubtless, many exceptions to this rule, but still I think our 
own experience establishes it as generally correct. Now, may it not 
be suggested that the same causes, whatever they may be, which 
tend to produce more brilliant colour, tend also to lessen sweetness 
of scent, and vice-versa ? and in tropical regions we know the scent 
of the comparatively dull-coloured flowers is particularly powerful. 
_ The, perhaps, greater number of brilliant-coloured scentless flowers 
found in a state of nature in our own climate, at least, I think, 
_ may be in part accounted for by the visits of butterflies, &c. ; for 
