BY THE REV. W. WOOLLS. 59 



leaves, and they recognise the difficulty of relying on brief 

 descriptions, which, according to the judgment of different 

 observers, were sometimes applied to very different trees. In 

 referring to some of the lists which were published half a century 

 since, it is amusing to notice the mistakes that occurred in the 

 misapplication of botanical names. Thus, for instance, the blue- 

 gum (E. saliyna) was referred to E. piperita, or the peppermint ; 

 the stringy-bark (E. capitellata or E. eugenioides) to E. robusta the 

 swamp mahogany ; white gum (E. hcemastoma) to E. tereticornis, 

 grey gum or bastard box ; and spotted gum (E. maculata) to E. 

 hcemastoma. It is no wonder that the systematic arrangement 

 proved so fallacious, when it is considered that the operculum, 

 even in the same species, is subject to variation, and that the 

 leaves are of various shapes and sizes on the same kind of trees. 

 This is seen in some species more than in others, whilst, as Mr. 

 Bentiiam found, as the result of long observation, that no sure 

 diagnostic characters could be taken from such sources. It is true 

 that in some species the venation is well defined, and that even 

 a few may be determined by the shape of the leaf, but these 

 are exceptional cases ; and perhaps of all known genera no 

 genus affords less assistance to the systematic botanist in the 

 character of its foliage than Eucalyptus. When, therefore, so 

 many difficulties presented themselves from previous endeavours 

 to classify our Eucalypts, Baron Mueller's plan of grouping them 

 according to the nature of their bark was hailed with satisfaction 

 by observers in these colonies. The system, it is true, cannot be 

 appreciated by European botanists, or those who have not an 

 opportunity of seeing the trees in a living state; but to persons who 

 are studying the species as they appear in their native forests, it 

 affords an easy method of referring them to a recognised position. 

 Besides, the terms "Gums," "Stringy-barks," and "Iron-barks" are 

 so natural and familiar to the colonists, that any system founded 

 on the smooth, fibrous, or rugged character of the bark, commends 

 itself to them. The cortical system, therefore, has proved a step 

 in the right direction, and it may be regarded as a popular method 

 of overcoming some portion of the difficulty which has attended 



