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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



gardeners are more or less scientific physiologists, though, 

 perhaps, without knowing it. For, it is just because florists 

 and horticulturists do succeed so wonderfully well in growing 

 plants that they have discovered for themselves what their 

 plants require ; without, it may be, exactly knowing the why 

 and the wherefore in every case. Their profession might, 

 indeed, be called " practical vegetable physiology." 



What science can add to the gardener's knowledge and 

 experience is, on the one hand, a full description of the minute 

 anatomy of plants, discovered after long and careful micro- 

 scopical examination of them ; and secondly, the several functions 

 of the different tissues, and thence the functions of all the plant 

 organs which are built up of those tissues. 



If, then, a gardener understands this, it is for him so to 

 place his plants, and so to feed them, as to secure to the fullest 

 possible amount the complete activity of each and all the plant 

 organs. 



It must always be remembered that no absolutely perfect 

 conditions can be secured ; but the cultivator can always 

 endeavour to obtain approximately the best ; and these the 

 grower can often find out where a scientist has no opportunity 

 of telling him. Thus, e.g., all green plants require light ; but 

 the amount that each requires as best for it is not the same for 

 all. This the Aucuba japonica illustrates very well; for the 

 leaves on the surface of a bush, and most exposed to light, are 

 much more spotted with yellow, which increases with a prolonged 

 intensity, than are the leaves more deeply situated within the 

 bush. These are always of a darker green and have fewer spots. 

 Conifers, too, often show a marked susceptibility to too strong a 

 light, when the colour of the foliage turns to a yellow green. 



The adaptations of plants to their surroundings should be 

 studied much more than has been the case. Thus, when 

 collectors introduce new plants from foreign countries, they 

 should always record accurately in their note-books the con- 

 ditions under which the plants were growing in their native 

 homes ; not only the nature of the soil, but the amount of light 

 or exposure to the sun, the amount of moisture or its absence, 

 &c. ; because the natural and healthiest conditions of plants in 

 the wild state are solely due to their having become thoroughly 

 adapted to those conditions ; and the nearer the cultivator can 



