BETULACEAE. 3 2 7 



at the base, strongly veined and about 2.5 cm. long when mature, its middle lobe 

 lanceolate, 2-4 times as long as the lateral ones, incised-dentate on one side, often 

 Dearly entire on the other ; nut 4 mm. long. In moist woods and along streams, 

 N. S.'to Ont., Minn., Fla. and Tex. April-May. 



2. OSTRYA Scop. 



Trees similar to the Hornbeams, the aments expanding with or before the leaves. 

 Staminate aments sessile at the ends of branchlets of the preceding season; fila- 

 ments 2 -cleft. Pistillate aments small, terminal, erect, the flowers 2 to each bract, 

 subtended by a tubular, persistent bractlet which enlarges into a nerved, bladder- 

 like sac in fruit. Style slender; stigmas 2, subulate. Nut ovoid-oblong, com- 

 pressed, smooth, sessile in the base of the inflated sac. Mature pistillate ament 

 hop-like. [The ancient name.] Four species, the following, 1 in the Southwest, 1 

 in Europe and Asia, 1 Japanese. 



1. Ostrya VirginianaCMill.) Willd. Hop-hornbeam. Iron-wood. (I. F. f. 

 1208.) Bark scaly. Twigs pubescent. Leaves ovate or oblong-ovate, acuminate, 

 the base rounded or inequilateral, sharply and doubly serrate, sparingly pubescent 

 above, pubescent or tomentose beneath, 6-15 cm. long; petioles rarely more than 

 4 mm. long; staminate aments 3-7.5 cm. long, their bracts triangular-ovate, acumi- 

 nate; bractlet of each fertile flower forming a sac 12-16 mm. long in fruit, cuspi- 

 date, pubescent, villous near and at the base with bristly hairs, finely reticulated; 

 nut 5 mm. long, shining; ripe fertile aments 4-7 cm. long. In dry woods, Cape 

 Breton I. toS Dak.. Fla., Neb. and Tex. April-May. Fruit ripe July.-Aug. 



3. CORYLUS L. 



Shrubs or small trees, with broad thin serrulate or incised leaves. Staminate 

 aments sessile at the ends of twigs of the previous season, expanding much before 

 the leaves, the flowers with about 4 stamens and 2 bractlets; filaments 2-cleft or 2- 

 divided, each fork bearing an anther-sac, which is villous at the summit. Calyx 

 none. Pistillate flowers from scaly buds, clustered at the ends of short branches of 

 the season, each in the axil of a bract, consisting of an incompletely 2-celled ovary 

 adnate to a calyx, a short style and 2 slender stigmas ; bractlets 2, enlarged in fruit, 

 forming a leaf- like involucre to the nut. Nut ovoid or oblong, bony. [Name Greek, 

 from the helmet-like involucre.] Species 7, in the northern hemisphere. Besides 

 the following, another occurs in California. 



Involucre of 2 broad laciniate bractlets. 1. C. Americana. 



Involucral bractlets united, prolonged into a tubular bristly beak. 2. C. rostrata. 



i. Corylus Americana Walt. Hazel-nut. (I. F. f. 1209.) A shrub, 0.8- 

 2.5 m. tall, the young shoots russet-brown, densely hispid-pubescent with pinkish 

 hairs. Leaves ovate or broadly oval, acute or acuminate, serrulate all around, cor- 

 date or obtuse at the base, finely tomentose beneath, 0.7-1.5 dm. long; petioles 4-8 

 mm. long; staminate aments mostly solitary, 7-10 cm. long; involucre of the nut 

 compressed, the 2 finely pubescent leaf-like bractlets laciniate on their margins, 

 commonly broader than high; nut compressed, light brown, striate, 1-1.5 cm. high. 

 In thickets, Me. and Ont. to Man., Fla. and Kans. March-April. Nuts ripe July- 

 Aug. 



2. Corylus rostrata Ait. Beaked Hazel-nut. (I. F. f. 12 10.) A shrub, 

 similar to the preceding. Leaves ovate or narrowly oval, incised-serrate and serru- 

 late, glabrous, or with some scattered appressed hairs above, sparingly pubescent 

 at least on the veins beneath; 2-6 cm. wide; involucral bractlets bristly-hairy, united 

 to the summit and prolonged into a tubular beak about twice the length of the nut, 

 laciniate at the summit; not ovoid, scarcely compressed, striate. In thickets, N. S. 

 to Br. Col., Ga., Tenn., Kans. and Ore. April-May. Fruit ripe Aug. -Sept. 



4. BETULA L. (See Appendix.) 



Aromatic trees or shrubs, with dentate or serrate leaves, scaly buds and flowers 

 of both kinds in aments expanding before or with the leaves. Staminate flowers 

 consisting of a membranous, usually 4-toothed perianth, 2 stamens, and subtended 

 by 2 bractlets; filaments short, deeply 2-cleft, each fork bearing an anther-sac. 

 Pistillate flowers 2 or 3 (rarely 1) in the axil of each bract, the bracts deciduous 



