Page:Enquiry into plants (Volume 1).pdf/161

 dry up. Most obvious are certain changes in regard to the way in which animals are produced, and such changes run through a series of creatures ; thus a caterpillar changes into a chrysalis, and this in turn into the perfect insect; and the like occurs in a number of other cases. But there is hardly anything abnormal in this, nor is the change in plants, which is the subject of our enquiry, analogous to it. That kind of change occurs in trees and in all woodland plants generally, as was said before, and its effect is that, when a change of the required character occurs in the climatic conditions, a spontaneous change in the way of growth ensues. These instances must suffice for investigation of the ways in which plants are produced or modified.

V. Since however methods of cultivation and tendance largely contribute, and, before these, methods of planting, and cause great differences, of these too we must speak.

And first of methods of planting as to the seasons, we have already stated at what seasons one should plant. Further we are told that the plants chosen should be the best possible, and should be taken from soil resembling that in which you are going to plant them, or else inferior ; also the holes should be dug as long as possible beforehand, and should always be deeper than the original holes, even for those whose roots do not run very deep.

127