Procccdliio^s of the Ohio State Academy of Science 157 



Flowers solitary or in twos, appearing before the leaves; fruit vel- 

 vety, stone compressed : leaves ovate to round-ovate, abruptly 

 pointed ; terminal bud of twigs absent. P. aniicniaca. 



Leaves mostly convolute in vernation ; fruit usually large ; stone 

 more or less flattened ; terminal bud of twigs absent. 3. 



Leaves conduplicate in vernation ; fruit mostly small ; stone mostly 

 glol)ose ; terminal bud of twigs present. 8. 

 3. Lea\'es abruptly acuminate; drupe red or yellowish. 4. 



3. Leaves obtuse, acute, or gradually acuminate: drupe red or purple. 6. 



4. Calyx lobes entire, pubescent within; drupe globose; leaves ovate 



or obovate. P. aincriccina. 



4. Calyx lobes glandular-serrate; drupe subglobose or oval. 5. 



5. Calyx lobes glabrous within; leaves oval or obovate. P. nigra. 

 Calyx lobes pubescent on both sides ; leaves ovate-lanceolate. P. 



Iiortiilaiia. 

 G. Leaves glabrous when mature, acute or acuminate. 7. 

 G. Leaves pubescent beneath, not jiointed, (ivate or obovate. P. do- 

 mestic a. 



Leaves lanceolate ; drupe red, thin-skinned, with little or no bloom. 

 /■". inigiistifolia. 



Leaves ovate; drupe dark purple with a ])loom. P. allcglnmiensis. 



Leaves glabrous ; inflorescence umbellate : drupe with thick flesh, 

 sour. P. cerastts. 



Leaves glabrous, shining; inflorescence more or less corymbose; 

 drupe with thin sour flesh. P. fcnusyl7'a>iiia. 



Leaves pubescent beneath at least on the veins : inflorescence um- 

 bellate ; fruit sweet. P. avium. 



Fruit red or purple, astringent ; leaves obovate or oval, abruptly 

 acute or acuminate, thin; glands on the petiole usually rounded or 

 disc-like ; bark gray. P. virginiana. 

 9. Fruit dark-purple or black, sweet: leaves oval or obovate, acute 

 or obtusish, thick ; otherwise much like the preceding. P. demissa. 

 9. Fruit dark-purple or black, sweet; leaves oval-lanceolate to ovate, 

 acuminate or acute ; glands on the petiole usually elongated and 

 tooth-like ; bark black. P. scrnthia. 



Plums and Apricot. 



'■■\ Prunns armeniaca T.. Apricot. A small round-topped 

 tree with reddish bark. Drupe nearly smooth, short stalked, yel- 

 low, edible. Cultivated. 



I. Prunus americana ]\l.arsh. Wild Plum. A shrub or 

 small tree with stunted thorn-like l)ranches and thick black bark. 



