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slightly from each other in this respect. A large number 

 of adult men placed in a row would give a similar picture 

 of variability. Again if we examine and carefully measure 

 the leaves on a tree, we find a few unusually large, and a few 

 unusually small, specimens, while the great majority are 

 intermediate and of moderate dimensions. The-same thing 

 occurs in the shape and size of seeds and fruits. Numbers 

 also vary in the same way, as is seen in the number of lateral 

 veins in leaves and leaflets. Small numbers, however, are 

 usually more constant than large numbers and a considerable 

 degree of constancy usually characterises the numbers of the 

 different floral organs. Such characters as the percentage 

 of sugar in the sugarcane, or of starch in potatoes, as well as 

 the power of resistance to frost, and so on, obey the same rule, 

 and we may say that this phenomenon of Fluctuating Vari- 

 ability is almost universal. This type of variation is obviously 

 directly dependent to a great extent on nutrition, and therefore, 

 indirectly, depends on the factors which together constitute the 

 plant's environment. On vigorous, well-nourished coppice 

 shoots the leaves are as a rule considerably larger than on 

 normal branches, while gardeners know that, by diminishing 

 the total number of flowers or fruits on a plant, and by thus 

 increasing the amount of food available for the remainder, the 

 size of the latter can be materially increased. The various 

 factors of the environment also Have a marked effect. A plant 

 accustomed to a damp locality, on being transferred to a dry 

 one, may be so changed in appearance as to resemble another 

 species. In such cases the size of the leaves and the 

 growth in length of all shoots are often greatly reduced 

 and thorns and spines are frequently developed. The common 

 Brinjal (Solanum Mdongena), for instance, when cultivated in a 

 well-watered garden, has large leaves which are often almost 

 unarmed. It may, however, be often seen as an escape from 

 cultivation, in dry rocky places, with small and intensely 

 prickly leaves. In India also we have several examples of 

 plants which, in dry localities, are erect shrubs, or small trees, 

 and in damp situations climbers such as Toddalia aculeata and 

 Alangium Lamarckii. The nature of the soil also frequently 

 appears to affect plant characters, and individuals growing in 

 soil containing large quantities of lime, or other substances, 

 may differ very considerably from individuals of the same 

 species growing in ordinary soil. Light is also a factor affect- 

 ing the form of plants, although it is sometimes difficult to 

 decide how far an observed result is to be ascribed to any one 



