Proceeding's of the Ohio State Academy of Science 109 



1/. Stamens of the same number as the petals and opposite 

 them ; ovulary 2-5-locular, calyx 4-5-cleft, valvate in the 

 bud ; petals involute ; fruit a drupe or capsule ; shrubs, 

 small trees, or vines with simple leaves. Rhamnaceae. 



a. Rhamnus. (60). 



18. Carpels i or more, united, but styles and stigmas may be 



several. 19. 

 18. Carpels more than i. distinct; filaments shorter than the 



anthers ; perianth trimerous ; leaves 2-ranked. Anon- 



ACEAE. 



a. Asimina. (34). 



18. Carpels numerous spirally arranged and cohering over each 



other, forming an aggregate cone-like fruit ; trees ; sepals 

 and petals in threes ; twigs with stipular rings. Magnol- 



lACEAE. 



a. Anthers introrse ; leaves not truncate. Magnolia (32). 

 a. Anthers extrorse ; leaves truncate. Liriodendron. (33). 



19. Ovulary compound, plurilocular. 20. 



19. Ovulary i-locular, 2-ovuled ; fruit a drupe with i seed. 



ROSACEAE. (DrUPATAE). 



a. Drupe glabrous, stone smooth or nearly so. 



Prunus, (42). 

 a. Drupe velvety, stone deeply pitted. Amygdalus (43). 



20. Calyx deciduous ; flower cluster subtended by a large mem- 



branous bract ; trees with alternate, 2-ranked leaves and 

 mucilaginous sap. Tiliaceae. 



a. Tilia. (16). 



20. Leaves alternate with deciduous stipules ; ovulary composed 

 of 2-5 wholly or ])artly united carpels ; fruit a more or 

 less fleshy pome. Rosaceae. (Pomatae). 

 a. Ripe carpels papery or leathery, b. 



a. Ripe carpels bon}'. Crataegus. (41). 



b. Leaves pinnate. Sorbus. (3^). 



b. Leaves sim])le. c. 



c. Cavities of the ovulary as many as the styles, d. 



