(76) 



8. Iva. — Involucre gainophyllus. Head an- 

 drogynous. 6 flowers funnel-sliaped, 

 central; $ flowers tubular, peripheral. 



9. Platanus. — Flowers without perigonium, 

 densely capitulate on a globose recep- 

 tacle. Tree. 



D. Floicers incomplete; $> flowers amentaceous. 



Stamens inserted on a perigonium. 



1. Castanopsis. — Involucre of ? flowers 1-3- 



flowered, afterward enclosing the nut 

 in the shape of a prickly burr. 



2. Quercus. — Involucre of ? flowers 1-flow- 

 ered, surrounding the base of the nut 

 in the shape of a cup. Trees. Shrubs. 



E. Flowers incomplete. S floivers or both ? 



and S , amentaceous. Stamens inserted 

 on bract. 



1. Corylus. — Fruit a nut, inclosed in a 2- 

 cleft, laciniate involucre. 



2. Myrica. — ? flowers amentaceous. Fruit, 

 drupaceous nutlets. Involucre 0. Tree. 



DICE CIA. 



Diandria. 



1. Salix. — Amentaceous. Perigonium 0. 

 Fruit an oo-seeded capsule. Shrub. 



2. Fraxinus. — Flowers paniculate. Calyx 

 obsolete, 4-cleft. Fruit a 1 -seeded 

 samara. Tree. 



