INTRODUCTORY ESSAY. 35 



and perpetuated by cuttings. Similar examples are afforded 

 by all our domestic fruit-trees^ among which, by a practised 

 eye, many different sorts can be recognized at once. 



In conclusion, the majority of our readers will smile when 

 we add that the general impression of persons of intelligence, 

 that they know our common English trees at first sight, is to 

 a great degree illusory : we have all an ideal Oak, Elm, Pop- 

 lar, etc., and we call the specimens that do not come up to 

 that ideal abnormal, and representations of such we say are 

 not characteristic ; but let any one keep a watch upon himself 

 in the fields, parks, or forests of countries not his own, yet 

 tenanted by trees specifically the same as those of his own, 

 and we venture to assert that he wiU find his preconceived 

 ideas fall to the ground in very many cases. We. do not 

 mean to say that he will not recognize a park oak, churchyard 

 yew, or weeping willow; but we do assert that he wiU not 

 recognize by habit the same oak at the Cape of Good Hope, 

 where it is now abundant, or the same yew in a thick forest ; 

 and we may add that no Himalayan traveller within our ex- 

 perience has, on his return to England, ever recognized the 

 Deodar at Kew Gardens by habit to be the plant of those 

 mountains, and that, on the contrary, we have frequently had 

 the Cedar of Lebanon pointed out as that tree. 



It is very much to be wished that the local botanist should 

 commence his studies upon a diametrically opposite principle 

 to that upon which he now proceeds, and that he should en- 

 deavour, by selecting good suites of specimens, produced under 

 all variations of circumstances, to determine how few, not how 

 many species are comprised in the flora of his district. The 

 permanent differences will, he may depend upon it, soon force 

 themselves upon his attention, whilst those which are non- 

 essential will consecutively be eliminated. There is no better 

 way of proving the validity of characters than by attempting 

 to invalidate them. The unavoidable tendency of the human 

 mind, when occupied with the pursuit of miaute differences, is 

 to seize on them with aridity, and to relinquish them with re- 



