BOTANICAL NOTES ON BRITISH FOREST TREES. 329 



Fruits somewhat like those of Birch, but more nut- 

 like, and not winged. 



Wood best distinguished from that of the Birch 

 by the narrower and deeper medullary rays on tangential 

 sections. 



Seeds fused with pericarp j only one ripens. Seedling 

 like that of Birch, but larger, and first leaves less hairy. 



9. BIRCH. 

 Betula alba (L.). Betulacese. 



Erect slender tree, with more or less pendent twigs, 

 with smooth purplish cortex covered with lenticels and 

 glands. 



Periderm flaking off in silvery paper-like layers. Base 

 of old trunks with very rugged, deeply fissured, hard 

 bark. 



Buds small, ovoid, pointed, smooth, purplish-brown. 



Leaves petiolate, pendent, rhomboid, triangular to 

 ovate acuminate, irregularly bi-serrate, dark green above, 

 often glandular when young. 



Flowers in monoecious pendent catkins, the male 

 being the longer and larger ; both visible in winter, and 

 opening before the leaves in spring. Female flowers 

 in threes. 



Fruits small, flat, laterally winged by relatively broad 

 membranous expansions, in the axils of trilobed com- 

 pound scales. 



Wood pinkish white, with very fine vessels and 

 narrow, but visible, medullary rays ; pith flecks 

 common. 



