178 DRUPACEAE 



b. Inflorescence corymbose : drupes less than 7.5 mm. in diameter. 



8. P. Pennsylvanica. 



B. Flowers in racemes terminating leafy branches of the year. 

 Racemes corymb-like. 9- P- Mahaleb. 

 Racemes elongated. 



Sepals deciduous : leaf-blades with sharp somewhat spreading teeth : 

 drupe mainly astringent. 

 Stone smooth : petals less than 5 mm. long. 10. P. Virginiana. 



Stone roughened : petals over 5 mm. long. 11. P. Padtis. 



Sepals persistent : leaf-blades with appressed blunt teeth : drupe mainly 

 sweet. 12. P. serolina. 



1. Prunus Americana Marsh. Wii,D YELLOW OR Red P1.UM. (Man. 

 p. 524 ; I. F. f. 200J.) In woods and thickets, N. Y. to Mont., Fla. and 

 Colo. — Pennsylvania : Northampton ; Bucks ; Delaware ; Chester ; 

 Lancaster ; Luzerne ; Franklin ; Huntingdon ; Somerset ; Alle- 

 gheny. 



2. Prunus Allegheniensis Porter. Porter's Plum. (Man. p. 524; 

 I. F. f. 2012.) In thickets, Allegheny Mountains, Pa. — Pennsylvania : 

 Huntingdon, Barrens ; Clearfield ; Elk. 



3. PrunuB spinosa L. SLOE. Blackthorn. Buckthorn. (Man. 

 p. 525; I. F. y. 20i6.) Along roadsides, Mass. to Pa. and N. J. Nat. 

 or adv. from Eu. — Pennsylvania : Philadelphia ; Delaware. 



4. Prunus Cerasus L. Sour Cherry. (Man. p. 525 ; I. F. /. 2020.) 

 In woods and thickets, N. Y. and Pa., to the Gulf States. Native of Eu. 

 — Pennsylvania : Northampton ; Bucks ; Allegheny. 



5. Prunus Avium L. Wild or Sweet Cherry. (Man. p. 525 ; I. 

 F. /. 2021. ) In thickets and woodlands, Conn, to Pa. and the Gulf 

 States. Native of Eu. — Pennsylvania : Northampton ; Bucks ; Mont- 

 gomery ; Lackawanna ; Allegheny. 



6. Prunus cuneata Raf. Appalachian Cherry. (Man. p. 525; I. 

 F. y. 201S.) In wet soil, or among rocks, N. H. to Minn., N. C. and 

 Wis. — Petmsylvania : Northampton ; Lancaster, N. Texas ; Chester. 



7. Prunus pumila L. Sand or Dwarf Cherry. (Man. p. 525 ; 

 I. F. /. 201 J.) On sand or gravelly shores, N. B. to Man., N. J. and 

 Mich. — Pennsylvania : Northampton ; Bucks ; Allegheny. 



8. Prunus Pennsylvanica L- f. Wild Red or Pin Cherry. 

 (Man. p. 526; I. F. /. 2022.) In rocky woods and clearings, Newf. to 

 Ga., west to the Rocky Mts. — Pennsylvania : Pike; Monroe ; North- 

 ampton ; Schuylkill ; Luzerne ; Blair ; Cambria ; Erie. 



9. Prunus Mahaleb L. Perfumed Cherry. (Man. p. 526 ; I. F. /. . 

 2023.) Thickets and waste places, N. Y. and Pa. Adv. from Eu. — 

 Pennsylvania : Lancaster ; Northampton ; Franklin. 



10. Prunus Virginiana L- Choke Cherry. (Man. p. 526; I. F. /. 

 2024.) Aloug river banks and in rocky situations, Newf. to Man., B, 



C, Ga., Tex. and Colo. — Pennsylvania: Pike; Monroe; North- 

 ampton ; Bucks ; Schuylkill ; Berks ; Montour ; Tioga ; Lehigh ; 

 Chester ; Delaware ; Allegheny. 



