Class XII. Order IV. 119 



in terminal corymbs. Calyx leaves linear. About fences and 

 thickets. May, June. 



TRIGYNU. 



147. SORBUS. 

 SORBUS AUCUPARIA. Mich. Mountain Ash. 



Leaves pinnate, smooth, leafets equal, serrate, 

 flowers coryiubed. 



Syn. PTRUS AUCUPARIA. Sm. Fl. Brit. 

 SORBUS AMERICANA. Muhl. 



An ornamental tree, much cultivated. Bark smooth. Leaves 

 pinnate, serrate, entire at base, smooth on both sides. Flow- 

 ers white, in large, terminal corymbs. In the European tree, 

 the one commonly cultivated, the young leaves are pubescent or 

 downy underneath. In the American, which is perhaps a dis- 

 tinct species, they are perfectly glabrous. Styles three, some- 

 times more. Berries red, lasting all winter. Grows native at 

 Cape Ann, and in Worcester county. May. 



148. PYRUS. 

 PTKUS ARBUTIFOLIA. Willd. Choke, berry. 



Leaves obovate, acuminate, serrate, downy un- 

 derneath, the midrib glandular above ; flowers in 

 corymbs. Willd. 



Syn. MESPILUS ARBUYIFOLIA. Lin. Midi. 



A slender shrub. Leaves oblong, oval or obovate> finely- 

 serrate, the midrib spotted on the upper side, with small, dark 

 glands. Flowers white, in compound, downy corymbs. Fruit 

 'with five cells and ten seeds, of the size of large whortleber- 

 ries, rough and astringent to the taste. Low woods and thick- 

 ets May, June. 



