68 FIELD AND WOODLAND PLANTS 



occupied by small, green fruits, spotted with brown, with a two- 

 chambered, brittle core. 



The White Beam (P. aria) is a small tree, commonly found on 

 the outskirts of woods on chalky or limestone soils, which might 

 be confused with the last species. It has large, irregularly-lobed 

 leaves, white and downy beneath, with serrate edges. The general 

 form of the leaf is egg-shaped, while that of the Service Tree is 

 cordate. The corymbs of white flowers bloom in April ; and the 

 fruit, though much Hke that of P. torminalis, is spotted with red. 



THE MOUNTAIN ASH. 



There are no less than four varieties of this tree, distinguished 

 mainly by the forms of the leaves, the serration of their edges, and 

 the number of lateral veins. 



We have yet another representative of the Rose order in the 

 Mountain Ash, Rowan, or Fowler's Service Tree (P. Aucuparia), 

 which is common in mountainous woods, and supplies an edible fruit. 

 It is a very graceful and beautiful tree, with a smooth gre3dsh 

 bark ; and pinnate leaves with from thirteen to seventeen serrate 

 leaflets, downy on the under side. The flowers are small, of a 

 creamy white colour, in large corymbs. They bloom in May and 



