Woodruffe-Peacock : The Rock-Soil Method. 



41 



We find it may be classed as follows : — 

 I. For protection only. 

 4. Where protected only. 



7. By roadside very common ; by grassland rare ; by 



tilth very rare. 



8. Fairly common. 



II. Quarries and gravel pits. 



14. Marine, where there are comminuted shells, or the 



sea sand is slightly mixed with silt. 

 16. In Lincolnshire our greatest elevation is 550 feet 

 only, and the soil pure chalk. Ballota under the 

 circumstances, does not clearly find its altitude limit. 

 In West Yorkshire, Mr. F. A. Lees now gives it a 

 range of o to quite 600 feet, he writes to me. 

 To sum up, Ballota would appear to be areal* in Lincoln- 

 shire, but it can only survive when unconsciously protected 

 by man, for its natural requirements, a bushy, open, limy, 

 lightly stocked soil is practically not to be found in this country. 

 That it is also local-areal in its soil requirements I cannot deny. 

 That it is extra-areal I cannot believe from my present informa- 

 tion, for w^hat advantage does it obtain from the neighbourhood 

 of villages, but protection from the feeding of stock ? It 

 certainly bears no relation to true (i) followers of man, like 

 Cheledonium, Hyoscyamus, Parietaria, etc., or of (2) Cultivation, 

 or of (3) Commerce. I m.ust, however, own the exact position 

 of Ballota is most difficult to determine. We are not helped 

 in the least by what Mr. S. T. Dunn says of itf : — 'A native 

 of the Mediterranean region and Western Asia. In England 

 and most of Europe it is a weed of hedges and w^aste places, 

 showing preference for the neighbourhood of human habitation.' 

 What does such writing tell us of the conditions of soil, stocking, 

 etc., of everything we require to form an accurate estimate of 

 the environmental conditions of Ballota abroad. 



The true fact about it is, that it seems to be influenced as 

 to its present place of growth by a cause I have never met with 

 referred to in floras. England was an open country, practically 



* Areal means adapted to the environmental conditions of any given 

 limit, field, village, county, or kingdom, without any suggestion of the 

 original place or conditions of evolution, or method of reaching the localit}^ 

 referred to. Local areal means the same, limited by some condition or 

 requirement of soil, moisture, stocking, etc. Extra areal vs\%'a.ws, \\\^ species 

 cannot, without conscious help on the part of man, survive in a limited local 

 environment. 



f ' Alien Flora,' p. 151. 



1909 February i. 



