183 



SUMMER KEY TO THE SPECIES. 



Page. 

 1. Leaf -petioles winged; leaflets with entire margins except near apex, ..R. copallina 186 



1. Leaf -petioles not winged; leaflets either with entire or serrate margins, 2 



2. Leaflets 7-13, with entire margins H. Vernix 184 



2. Leaflets 11-31, with serrate margins, 3 



3. Leaflets glaucous beneath; twigs smooth; shrubs, R. glabra 183 



3. Leaflets not glaucous beneath; twigs densely hairy; small trees R. typhina 185 



WINTER KEY TO THE SPECIES. 



1. Terminal bud present; fruit white, smooth, in loose, drooping, grape-like clusters 

 frequents swamps; leaf -scars broad, do not encircle buds; juice poisonous, .... 



R. Vernix 184 



1, Terminal bud absent; fruit red, hairy, in compact erect clusters; frequents dry soils; 



leaf -scars encircle or almost encircle buds; juice not poisonous, 2 



2. Twigs stout, with watery juice; leaf-scars broadly crescent-shaped R, copallina 186 



2. Twigs very stout, with milky juice; leaf -scars narrower 3 



3. Twigs densely hairy, R. typhina 185 



3. Twigs smooth R. glabra 182 



