324 J. H. MAIDEN. 



rence of these young or sucker leaves is so very frequent 

 in the bush. 



"When a trunk is injured new shoots make their appearance 

 either from the "eyes" in the stem or from reserve buds of the 

 branches and twigs, or by buds produced from the roots below 

 the ground. The leaves of these shoots or suckers, as they are 

 called, differ very much from the stems or branches which have 

 been broken, eaten, cut or frozen off." . 



Instances of differences are given and it is added, 

 "Hundreds of trees and shrubs might be mentioned in which there 

 is a distinct difference between the foliage of the suckers and of 

 the normal branches of the crown." 1 



Nor has the description of species and varieties from 

 suckers or seedling leaves been confined to writers on 

 Eucalyptus : — 



"Gardeners and descriptive botanists have frequently determined 

 and described mutilated plants as other species, hybrids, or varieties. 

 They are neither the one nor the other. The peculiar appearance 

 of the altered members resulting from mutilation is exactly 

 determined beforehand in each species; it is due to the specific 

 constitution of the species, and thus is part of its being. It is 

 not produced by the external influences which lead to the form- 

 ation of the varieties, but is brought about by the inherent 

 necessity quite independent of the influeDce of climate and soil." 2 



Practically all the researches on the anatomy of 

 Eucalyptus leaves have been made on those of the readily 

 available E. globulus, in which species both sucker and 

 mature leaves are readily available. 



The most complete research is the masterly paper of 

 G. Briosi. 3 See also a study by H. Pocklington. 4 



1 Kerner and Oliver, n., 515, 6. 2 Op cit., 518. 



3 Ricerche intorno all 5 anatomia delle foglie dell' Eucalyptus globulus, 

 23 pi. Milano, 1892. 



4 The Microscope in Pharmacy, Eucalyptus globulus, Pharm. Journ. (3) 

 in., 990; iv., 549. A useful histological study of bark, leaves, etc. 



