358 IX. ORDINAL SUMMARIES, 



be deemed to succeed each other in climate and position similarly with 

 the succession of t?ieir names in the above list. If we trace downwards 

 from the higher hills and more northerly provinces, towards the low or 

 flat country of the south-eastern provinces of England, we lose the 

 plants nearly in the order or series of tlieir names. Conversely, we may 

 meet with them nearly in accordance with the same series reversed, as we 

 pass from the low south-eastern provinces into the more boreal and more 

 mountainous provinces. But in no single province or division can the 

 same series be found. The plants themselves do not all occur in any 

 one province or larger division of Britain ; and in each separate division 

 or province some variations will appear in the succession of those which 

 do occur there. Moreover, progressive knowledge will doubtless induce 

 changes and corrections in the relative position or series of the names as 

 now printed. The list is restricted to those plants not marked " 1 " in 

 the ' Summary of Distribution,' that is, not certainly descending into the 

 inferagrarian zone. The Hieraeia are mostly omitted ; the statements 

 about their lower limits, in the Monograph by Mr. Backhouse, being 

 found too incomplete and uncertain for use in this manner. 



Possibly the short list of lower limits may prove a sort of Pons 

 asinorum with beginners. If more advanced botanists should find any 

 difficulty in understanding it, they are requested to read carefully the 

 lower halves of pages 164, T65, and the upper half of page 166. If 

 they should theu still fail to understand the list, they are respectfully 

 recommended not to trouble themselves about phyto-geography. 



IX. CENSUS OE SUMMARIES OF ORDERS. 



N.B. Comparisons would be found less convenient among the orders 

 in any one of the annexed lists, if they should be set iu a fragmentary 

 manner over more pages than actually required by the number of lines. 

 On this account the explanations will not be appended to each in turn, 

 but be given colleclively after the last of them. 



