29fi THE FLORA.. 



b Involucre none. Anthers 4-valved. Leaves lobed. Sassafras. RAS'SAFKAS. ] 

 b Involucre 4 leaved. Anthers 2-valved. Shrubs. Spice-busk. BKN'ZOIN. 



b Involucre 4-leaved. Anthers 4-valved. Shrubs. S. Pond-spice. TETRANTHE RA. 



SASSAFRAS. Sassafras. 



Flowers dioecious, 6-parted, regular. Stamens 9. Trees with decidu 

 ou? leaves, expanding after the clusters of yellow flowers. 

 S. officina'le. Common S. Leaves of two forms, ovate and entire, or 3-lobed and 

 acute at base. Tree aromatic, 10-30f. high. 



ORDER CXIX. CUPULIFER^E. The Mastworts. 



Trees 'or shrubs, with alternate, simple leaves, and deciduous stipules, 

 flowers monoecious, the sterile in aments, which are racemed or head-like ; 

 ttamens in the sterile flowers, 6 to 20, on the base of the calyx ; 

 ovary in the fertile flowers with several cells and ovules, but becoming in 

 fruit a 1-seeded nut surrounded by an involucre (cup, burr, or sac). 



Analysis of the Genera, 



S .Sterile flowers in atnents, fertile flowers solitary or 2 or 3 together 2 



8 Sterile flowers and fertile also in aments, the latter loose and large.... c 

 2 Involucre 1-flowered, cup-like, composed of many little scales.... a 

 2 Involucre 2 or 3-flowered, composed of few large valves.. . .b 

 * Sterile aments slender, calyx 5-cleft, stamens 5 or 10. Fertile flowers, con- 

 sisting of an ovary sitting in a scaly cup, becoming, in fruit, an acorn, 1- 

 celled, 1-seeded. A noble genus of trees (rarely shrubs), always known by 

 their peculiar fruit, called acorns. The timber is of great value, especially 

 in ship-building. In the Class Book of Botany, 23 species are described. 

 (See Figs. 32-34, 267.) Oak. QUERCUS. 1 



b Involucre of the fruit and fertile flowers a burr with 4 valves. Sterile aments 

 slender, each flower with 5-15 stamens ; 3 fertile flowers in each involucre, 

 which is beset with slender prickles. We have two species, one a tree, the 

 other a shrub. Timber excellent. The fruit is sweet and nutritious. (See 

 Fig. 277.) Chestnut. CASTA'UKA- 



b Involucre of the fruit a burr with 4 valves. Sterile aments head-like, sus- 

 pended by a slender stalk. Calyx 6-cleft. Two .flowers in each burr, which 

 is covered by weak spines. Nuts sharply 3-angled. They are tall, valua- 

 ble forest-trees. Betch. FAOUS 

 b Involucre a sac, longer than the nuts, torn at the top. Sterile flowers in a 

 slender ameut. Shrubs. Usually but one flower or nut in each involucre. 



Hazel. OOR'YT.US. 



