HORNBEAM G.X. 6704 



HORNBEAM 



Carpi nus Betulus Linn. Betulaceae. 



A diffuse-porous wood of a white colour, very hard and heavy, showing 

 in transverse section the very marked undulating contour of the rings. 

 A sapwood tree. 



Transverse section. Boundary, a line of contrast in the density of 

 succeeding rings, along which may be found a scanty line of small pores. 

 Contour as above, in bold waves which become more accentuated as 

 the tree ages. This particular contour has nothing to do with the shape 

 of the pith, as is sometimes stated. 



Parenchyma (a) vasicentric, very scanty and invisible with lens, and 

 (b) in fine bars between the rays, very scanty also (needs microscope). 



Vessels very small (lens), those of the boundary a little the larger: 

 those of the greater part of the ring minute and disposed more or less 

 radially between the small rays. They thin out in the Autumn wood. 



Rays of two kinds (small and aggregate, i.e. bunches of small rays). 

 The aggregate rays are readily visible, white, casual in their occurrence, 

 being sometimes in groups, and at others absent over wide areas of the 

 section. The smaller rays need lens. 



Radial section. Very smooth and plain. Boundary sometimes ap- 

 parent. Vessels very fine. Rays broad, white flakes which contrast but 

 little with the ground. 



Tangential section. As the radial, but the rays are merely high spindle- 

 shaped bodies that are often obscure. 



Not easily confused with: May be distinguished by: 



Any other wood except perhaps Undulating contour of rings, 

 Holly which has rings of regular large rays which are few and 

 contour; rays numerous and regular casual, and high in tangential see- 

 in occurrence rarely exceeding tion (1 to several inches). The 

 \ inch high, in tangential section, small ones are uni- and multi- 

 and though small are multiseriate. seriate mixed. 

 Its silver-grain appears as very 

 narrow flakes. 



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