10 BETULACEAE. 



hoary on both sides: staminate aments less than 1 cm. long: capsules 5-6 mm. 

 long. DWARF GRAY-WILLOW. 



Woods and banks, n. Fla. (Cont.) Not recently collected in the state. 



Order FAGALES. 



Shrubs or trees. Leaves alternate: blades simple. Flowers monoe- 

 cious or rarely dioecious, at least the staminate borne in aments, the pis- 

 tillate sometimes with an involucre which becomes a bur or cup in fruit. 

 Calyx usually present. Corolla wanting. Fruit a nut or rarely a samara. 



Staminate and pistillate flowers in aments : fruit not with a bur or a cup. 



Staminate flowers solitary in the axil of each bract, without a calyx : pistillate 



flowers with a calyx. Fam. 1. COBYLACEAE. 



Staminate flowers 2-3 together in the axil of each bract, 



each with a calyx : pistillate flowers without a calyx. Fam. 2. BETULACEAE. 

 Staminate flowers in aments : pistillate often solitary, the 



involucre becoming a bur or cup. Fam. 3. FAGACEAE. 



FAMILY 1. CORYLACEAE. HAZEL-NUT FAMILY. 



Shrubs or trees, the wood close-grained. Leaves deciduous: blades 

 mostly doubly toothed. Staminate aments drooping, with each bract sub- 

 tending one flower, the calyx wanting. Pistillate aments not drooping, 

 each bract bearing 2 or 3 pistils, the involucre of a bract and 2 scales. 

 Fruit consisting of one or more accrescent bracts each subtending or inclos- 

 ing 1, 2 or 3 nuts. 



Fruiting bracts flat, 3-lobed, the terminal lobe toothed. 1. CABPINOS. 



Fruiting bracts bladder-like. 2. OSTBYA. 



1. CARPINUS [Tourn.] L. Trees or shrubs, the bark smooth. Stami- 

 nate aments solitary, the bracts acute, ciliate. Pistillate aments with 3-lobed 

 bracts at maturity. 



1. C. caroliniana Walt. Shrub, or tree becoming 13 m. tall, the bark blue- 

 gray: leaf -blades oblong, varying mainly to ovate or ovate-lanceolate, 3-14 

 cm. long, glabrous above: staminate aments 2-5 cm. long: mature bracts of 

 the pistillate aments hastate, 2-3 cm. long : nuts 5-6 mm. long. HORNBEAM. 

 Rich woods, n. Fla. and the upper pen. (Cont.) Spr. 



2. OSTBYA [Mich.] Scop. Shrubs or trees, the bark scaly. Staminate 

 aments clustered, the bracts blunt, not ciliate. Pistillate aments with lobeless 

 bracts. ; J. 



1. O. virginiana (Mill.) Willd. Shrub, or tree becoming 18 m. tall, the bark 

 rough: leaf -blades mainly oblong, elliptic, or oval, 3-13 cm. long, slightly 

 pubescent or glabrate above: staminate aments 3-8 cm. long: mature bracts 

 of the pistillate aments oblong to ovate, 1.5-2 cm. long: nuts 6-7 mm. long. 

 HOP-HORNBEAM. 



Rich woods, n. Fla. and upper pen. (Con*.) Spr. 



FAMILY 2. BETULACEAE. BIRCH FAMILY. 



Shrubs or trees, the wood close-grained. Leaves deciduous: blades 

 with 2 several series of teeth. Staminate aments drooping, with each 

 bract subtending 2 or 3 flowers, the calyx present. Pistillate aments 

 seldom drooping, the bracts thickened and woody, each one bearing 2 or 

 3 pistils, the calyx wanting. Fruit a cone-like aggregate of the accrescent 

 bracts each of which subtends a nut. 



