TEHON: FIELDBOOK OF NATIVE ILLINOIS SHRUBS 17 



M. Petals more or less united, 

 m. Ovary superior. 



n. Stamens free from the corolla. 

 o. Carpel 1; corolla irregular. Leguminosae, p. 144 



o. Carpels several, united ; corolla regular 



Ericaceae, p. 220 



n. Stamens more or less adnate to the corolla. 



p. Stamens 5 ; petaloid staminodes 5 



Sapotaceae, p. 236 



p. Stamens 4; staminodes, when present, not peta- 

 loid Bignoniaceae, p. 246 



m. Ovary inferior. 



q. Stamens twice, or more than twice, as many as the 

 corolla lobes. 



r. Ovary 1-celled Styracaceae, p. 239 



r. Ovary 4- to 10-celled Vacciniaceae, p. 228 



q. Stamens the same in number as the corolla lobes. 



s. Leaves joined by stipules Rubiaceae, p. 249 



s. Stipules wanting Caprifoliaceae, p. 252 



Key to Genera 



I. Leaves very narrow ; linear, or scalelike, and small. 

 A. Leaves evergreen, glabrous; more than ]/s inch long. 



a. Leaves apparently in 2 ranks; green above. . .Taxus, p. 25 



a. Leaves in whorls of 3 ; with a white line above 



Juniperus, p. 27 



A. Leaves persistent but not evergreen, pubescent; less than 



l4 inch long Hudsonia, p. 204 



IL Leaves broader, with proper blades; not pinelike. 

 A. Leaves simple, though often toothed or lobed. 

 B. Leaves opposite or whorled ; 2 or 3 at a node. 

 C. Leaf margins entire. 



D. Leaves and twigs densely coated with silvery or 



rusty scales Shepherdia, p. 208 



D. No silvery or rusty scales present. 

 E, Leaf blades with translucent dots. 



F. Branchlets round ; creeping shrubs 



Ascyrum, p. 200 



F. Branchlets 2-edged ; upright shrubs 



Hypericum, p. 201 



E. Leaf blades without translucent dots. 



G. Leaves often 3 at a node. . . . Cephalanthus, p. 250 

 G. Leaves definitely 2 at a node. 



H. Leaves thick; parasites growing on tree 



branches Phoradendron, p. 71 



H. Leaves normally thin ; not parasites. 



L Secondary veins running together near the 

 margins and meeting at the leaf tip; 

 leaves often mealy beneath. . . .Cornus, p. 212 



