Plate IV 



a. Quercus Rohm; Betula tomentosa, Fagus sylvatica, Firms sylvestris, 

 Pteris aquilina, Galluna vulgaris. Ashdowu forest, Sussex, on 

 AshdowD sand. 



phot, S. ^[angham 



b. Betula tomentosa, Pyrus Aria, Fagus sylvatica, Calluna vulgaris, 

 Pteris aquilina. Toy's Hill, Kent, on Hythe Beds, Lower Greensand. 



Oak-bircli heatli association. 



