428 BETULACE^. (birch FAMILY.) 



Drupe oblong, obtuse, narrowed at the base : epicarp thick, coriaceous, smooth : 

 endocarp crustaceous. Albumen none. Embryo large, filling tlie cell. Coty- 

 ledons oval, compressed. Radicle superior. — A stout shrub, 2° -6° high, with 

 soft wood and smooth light-brown bark, without resinous dots. Branches short 

 and thick, hoary-pubescent when young. Leaves oblong or obovate-oblong (4'~ 

 6' long), acute at each end, entire, smooth and shining above, hoary-tomentose 

 beneath, straight-veined, on long spreading or recurved hoary petioles, decidu- 

 ous. Stipules none. Aments developed before the leaves, from the axils of the 

 preceding year, the sterile ones 1'- 1^' long, the fertile 6" -8" long. Drupe ^' 

 long, green, slightly curved. 



1. L. Floridana. — Salt or brackish marshes, Apalachicola, Florida.— 

 Feb. and March. 



Order 130. BETULACE^E. (Birch Familt.) 



Trees or shrubs, with alternate simple straight-veined leaves, deciduous 

 ptipules, and monoecious amentaceous flowers, placed 2-3 together in the 

 axil of a 3-lobed bract. Stamens 4 : filaments distinct. Ovary 2-celled, 

 with a single suspended anatropous ovule in each cell. Stigmas 2, elon- 

 gated. Fruit a winged or angled 1-celled 1-seeded nut, forming, with the 

 imbricated persistent bracts, a cone-like spike. 



1. BETXJLA, Tourn. Birch. 



Sterile aments drooping. Bracts 3-flowered, 2-bracteolate, peltate. Calyx 

 scale-like. Stamens short : anthers 1-celled. Fertile aments oblong or cylin- 

 drical. Bracts 3-flowered. Calyx none. Stigmas filiform. Nut broadly winged. 

 Cotyledons oblong. — Trees or shrubs, with the outer bark often separable into 

 thin papery sheets. Leaves petioled, serrate. Fruiting bracts membranaceous. 



1. B. nigra, L. (Black Birch.) Leaves rhombic-ovate, acute, doubly 

 serrate, smooth above, hoary-tomentose beneath, like the short petioles and 

 branchlets, becoming rusty or smoothish ; sterile aments long and drooping ; 

 the fertile ones oblong, short-peduncled, with the woolly bracts cleft into three 

 linear-oblong nearly equal lobes. (B. rubra, Michx.) — Banks of rivers, Florida, 

 and northward. March. — A middle-sized tree, with reddish-brown bark, and 

 long spreading branches. 



2. B. excelsa, Ait. (Yellow Birch.) Leaves ovate or oblong-ovate, 

 acuminate, unequally and doubly serrate, pubescent, like the branchlets, when 

 young, at length smooth on both sides, on short pubescent petioles ; fruiting 

 aments oval-oblong ; lobes of the bracts nearly equal, slightly spreading and 

 hairy, acute. (B. lutea, Michx.) — Mountains of North Carolina, and north- 

 ward. March and ApriL — A tree 40° - 60° high, with yellowish bark. Leaves 

 2' -3' long. 



3. B. lenta, L. (Chkrry Birch.) Branchlets smooth ; leaves ovate or 

 oblong-ovate, acute, cordate, finely and doubly serrate, silky when young, at 



