INTRODUCTION. 



two former conditions {i.e. the defoliation of trees, and, in extreme cases, 

 hibernation of animals). These natural seasons are most distinctly 

 marked the lower we go in the organic scale, but they are more or less 

 distinguishable throughout the vegetable and animal kingdoms. In our 

 temperate climate the season of growth or reproduction is in the spring 

 and early summer ; that of maturation is in the late summer and autumn ; 

 and that of rest in the winter months. The range of the seasons varies 

 with different species of plants, and they are further modified by various 

 natural and artificial conditions. Cultivation, with its numerous appliances 

 for modifying the physical conditions of temperature, moisture, and soil, 

 tends to a hastening or shortening of the earlier seasons — hence cultivated 

 plants generally blossom and fruit earlier than wild ones of the same 

 species ; and some meteorological conditions, such as high temperatures 

 and droughts — if they do not suspend vegetation altogether — shorten the 

 period of growth and hasten that of maturation, and sometimes give rise 

 to the exceptional phenomena of the second leafing and blossoming of 

 plants and trees in the same year. 



The order of the seasons differs with the relative length of the day 

 and night. Growth in length or bulk of vegetables takes place in thei 

 dark, while maturation of structures and juices takes place in the light ;l 

 hence the plants of arctic and alpine regions are dwarfed by the short,7 

 cold nights, and hastily matured (as shown by a profusion of blossoms)/ 

 by the long days of these regions, and there are few spring flowers because 

 the seasons pass quickly from winter to summer. In the tropics, on the 

 other hand, where the days and nights are of nearly equal length and the 

 temperature is always favourable, growth is almost continuous (hence an 

 excess of leaves over flowers), and is interrupted only by lack of moisture, 



Much of the irregularity in the blossoming of plants and trees in our 

 climate is no doubt due to the introduction, by what is called acclimatiza- 

 tion, of numerous plants belonging to other latitudes. The early blos-| 

 soming plants, such as the winter aconite, snowdrop, and spring crocus,! 

 belong originally to warm, temperate climates, where drought is a 

 more powerful agent in modifying vegetation than it is in our cold 

 and moist climate — their bulbous roots being a provision against drought 

 rather than low temperatures — and their blossoming corresponds, 

 therefore, with the wet seasons of their native regions rather than the 

 beginning of the warm season in our own. In like manner the cultivated 

 trees which blossom early with us, and at the risk of being destroyed by 

 our late frosts, such as the apricot and the peach, are natives of warmer 

 latitudes which persist in the habit of blossoming as near to the time they 

 would blossom in their native climates as ours will permit. 



The season of maturation is most distinctly displayed by the ripening of 

 fruits and seeds, but it equally applies to the ripening of the buds, roots, and 

 tubers of perennial trees and plants which cast their leaves or die down. 



The season of rest is best seen in our forest trees which shed 



