92 TREES AND SHRUBS "' 



2. CRATEGUS L. Hawthorn 



Shrubs or small trees with stout spiny stems, simple, alternate, 

 toothed or lobed leaves, and white flowers in corymbs; hypanthium 

 urceolate, adnate to the ovary; sepals 5, persistent; petals 5, spread- 

 ing; stamens 5 to 10; fruit small, drupaceous, having 2 to 5 bony, 

 1-seeded carpels. 



Spines short, % inch or less, not very numerous; 

 leaves mostly elliptic, not noticeably lobed, 

 the i lade about twice as long as wide. 1. C. rivularia. 



Spines longer, 1% inches or more, commonly 

 numerous; leaves broader, at least some of 

 them more or less lobed. 

 Leaves elliptic-ovate, rather coarsely serrate, 

 some of them with a few larger lobe-like 

 teeth, the smaller teeth gland-tipped; 

 leaves cuneate at the base. 2. C. cerronia. 



Leaves broadly ovate, with 3 to 4 pairs of 

 broad lobes, finely serrate or doubly ser- 

 rate with straight teeth, not gland-tipped; 

 base of leaves truncate. 3. c. wootoniana. 



3. SORBUS L. Mountain Ash 



- rub 3 to 10 feet high with pinnate leaves and white flowers 

 in compound cymes; hypanthium urceolate or turbinate; leaflets 

 11 to 15, 1 to 1% inches long, oblong-lanceolate, serrate, glabrous; 

 sepals 5; petals 5, spreading,short-clawed; stamens 20; styles 3 to 

 5, distinct, wooly at the base; fruit a berry-like pome. 

 A single species in the Transition Zone. l. S. scopulina. 



