BIRCH FAMILY. 



507 



2. OSTRYA Scop. Fl. Cam. 4,4. , 7 6o 



Trees similar to the Hornbeams, the trunks furrowed, tlu- prilMrj veins of the leave. 

 simple or forked, the aments expanding with or before the leaves. Staminate aments set 

 sile at the ends of branchlets of the preceding season, their flowers as in Carpinus, solitary in 

 the axil of each bract; filaments 2-cleft. Pistillate aments small, terminal, erect, the flowers 

 - to each bract, subtended by a tubular, persistent bractlet which enlarges into a membran- 

 es, nerved, bladder-like sac in fruit. Style slender; stigmas 2. subulate Nut ovoid-ol 

 long compressed, smooth, sessile in the base of the inflated sac. Mature- pistillate ament 

 hop like. [The ancient name.] 



Four species, the following, i in the Southwest, i in Murope and Asia, i Japanese. 



j. Ostrya Virginiana ( Mill.) Willd. Hop- 

 hornbeam. Iron-wood. (Fig. 1208.) 



1768. 



I'irginiana Mill Card. Diet. Kd. 8. 

 (hlrya I'irginica Willd. Sp. PI. 4: 469. 1805. 



A tree, with a maximum height of about 50, 

 trunk diameter of 2, twigs of the season pubescent. 

 Leaves ovate or oblong-ovate, the apex acuminate, 

 base rounded or inequilateral, sharply and 

 doubly serrate, sparingly pubescent and green 

 above, pubescent or tomentose beneath, a^ / -4 / 

 long, \'-\Vz f wide; petioles rarely more than 2" 

 long; staminate aments 1%'-$' long, their bracts 

 triangular-ovate, acuminate; anther-sacs villous at 

 the summit; bractlet of each fertile flower forming 

 sac 6"-8" long and 4 // ~5 // in diameter in fruit, 

 cute, cuspidate, pubescent, villous near and at the 

 ase with bristly hairs, parallel-veined and finely re- 

 ticulated; nut 2 Yz" long, compressed, shining; ripe 

 fertile ameuts erect or spreading, i> / -2> / long. 



In dry woods, Cape Breton Island to Minnesota, Florida and Texas. Wood similar to that of the 

 Hornbeam, but heavier; weight per cubic foot 51 Ibs. April-May. Fruit ripe July-Aug. 



3. CORYLUS L. Sp. PI. 998. 1753. 



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

 essile at the ends of twigs of the previous season, expanding much before the leaves, the 

 lowers solitary in the axil of each bract, of about 4 stamens and 2 bractlets; filaments a- 

 :left or 2-divided, each fork bearing an anther-sac, which is villous at the summit. Calyx 

 lone. Pistillate flowers from scaly buds, clustered at the ends of short branches of the ea- 

 3n, 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, remaining nearly distinct or united into a tubular beak. Nut ovoid or 

 oblong, sometimes compressed, large, bony. [Name Greek, from the h : -lmet-like involucre.] 



Species 7, in the northern hemisphere. Besides the following, another occurs in California. 

 Involucre of 2 broad laciniate bractlets; leaves serrulate. I. C. Atn,-i 



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



i. Corylus Americana Walt. Hazel-nut. 

 (Fig. 1209.) 



Corylns Americana Walt. Fl. Car. 336. 1788. 



A shrub, 3-8 tall, the young shoots russet- 

 brown, densely hispid-pubescent with pinkish hairs, 

 the twigs becoming glabrous. Leaves ovate or 

 broadly oval, acute or acuminate at the apex, serru- 

 late all around, cordate or obtuse at the base, gla- 

 brous or nearly so above, finely tomentose beneath, 

 3 / -6' long, 2'-4# / wide; petiole >ng; stam- 



inate aments mostly solitary, 3 '-4' long; involucre 

 of the nut compressed, composed of the 2 nearly 

 distinct finely pubescent leaf-like bractlets, which 

 are laciniate on their margins, commonly broader 

 than high and more or less exceeding the nut; 

 nut compressed, light brown, striate, #' high. 



In thickets. Maine and Ontario to Manit-> 

 and Kansas. March-April. Nuts ripe July 



