Woodhead : Botany at the British Association. 447 



during folding from one district to another. He suggested 

 that the lavas of the North of England and Scotland might have 

 originated under the Alps, and were carried to our Islands 

 during the uplift of the Alpine chain. 



Prof. Cole remarked that earlier geologists, such as Scrope, 

 recognised recumbent folds, and attributed their formation 

 to vertical upthrust of igneous cores and the slipping away 

 of sediments. He asked whether the epochs of mountain 

 building might not be due to some primordial periodic change 

 of temperature in the interior, remaining from the time when 

 our planet formed part of what we call a variable star. 



BOTANY AT THE BRITISH ASSOCIATION. 



T. W. WOODHEAD, Ph.D., F.L.S. 



As was anticipated, the president (Dr. F. F. Blackman) 

 naturally gave the section a strong physiological bias. His 

 opening address dealt with ' The Manifestations of the 

 Principles of Chemical Mechanics in the Living Plant," and 

 was followed by numerous papers by the president and his 

 students, which made a brave show, and one could not help 

 being impressed with the gr^^at activity that is going on 

 in the Botany School of Cambridge. The contributions of 

 chief interest to field naturalists, however, were by Mr. 

 A. G. Tansley and Dr. Moss on the Woodlands of England. 

 These were illustrated by vegetation and geological maps 

 of parts of south east England and Derbyshire, now 

 under investigation by the authors. Though the major paper 

 was by Mr. Tansley, they both brought out the same general 

 principles. An examination of the woodlands of the country, 

 with a view to grouping them in a natural way, shewed that 

 there remained very little (i) primitive woodland, but areas 

 existed which may be called (2) natural woodland, where, 

 though felling had occurred, they had been rejuvenated by 

 self-seeding of the former species. A more frequent type was 

 (3) woodland planted up with the type of tree natural to the 

 area. Often areas are (4) planted up with original species, 

 with an admixture of others as Sycamore among Oak. Other 

 types are (5) woods felled and planted up by new types, as 

 Oak replaced by Larch, and lastly (6), plantations de novo, 



1908 December i. 



