Class XII. Order I. 193 



larger and a fortnight earlier than those of P. Virginiana. Fruit 

 small, red, bitter, strong, and astringent. May. 



It differs from P. Virginiana, and P. serotina of Muhlenberg 

 and Willdenow, in its obovate and sharply serrated leaves, small 

 size, early flowering and red fruit. 



PRUNUS BOREALIS. Pursh. Northern Wild Cherry. 



Corymbs with elongated pedicels ; leaves oval-ob- 

 long, acuminate, slightly eroded, membranous, smooth ; 

 fruit subovate. 



Syn. CERASUS BOREALIS. MX. 



A small tree, with very thin, delicate leaves, and small, red, 

 astringent fruit On Blue hills, Milton. Common in Maine, 

 where it succeeds to pine forests, which have been cut down. 

 May. 

 PRUNUS DEPRESSA. Pursh. Sand Cherry. 



Umbels sessile, aggregate, few flowered ; branches 

 angular, prostrate ; leaves wedge-lanceolate, slightly 

 serrate, smooth, glaucous underneath ; fruit ovate. 



Syn. CERASUS FUMILA. MX. 



A small, trailing shrub, spreading its branches close to the 

 ground. On the shores of Lake Champlain. May. 



*PKUNUS LITTORALIS. Beach Plumb. 



P. umbellis conglomeratis, paucifloris ; pcduncu- 

 lis calycibusque subpubescentibus ; foliis ovalibus 

 acutis, serratis, venis subtus pubescentibus. 



Umbels crowded, few flowered ; peduncles and ca- 

 lyxes somewhat pubescent ; leaves oval, acute, serrate, 

 the veins pubescent beneath. 



Syn. PRUNUS SPHAEROCARPA. MX.? ncc Willd. 



A shrub with stout, straggling branches. Leaves scattered, 

 crowded, oval or obovate, acute, single and doubly serrate, 

 smooth or rugose above, slightly pubescent or tomentose be- 

 neath. Petioles short, pubescent, and biglandular. The flowers 

 appear before the leaves on the sides near the extremities of the 



