156 GENERAL BOTANY 



shape and margin. In Part II will be found descrip- 

 tions of common plants, and these should be carefully 

 gone through, with the specimens themselves. It 

 must always be remembered that variations occur in 

 all leaves. We must, therefore, try always to get hold 

 of the most usual or distinctive type and describe 

 that, and avoid abnormal cases. 



