TILIACEAE 761 



1. Tilia Americana L. A tree, reaching a maximum height of 40 m., with a trunk 

 diameter of about 1 m., the bark furrowed, its ridges flat. Leaf-blades firm, ovate or orbic- 

 ular-ovate, 8-15 cm. long, abruptly acuminate, serrate with acuminate gland-tipped teeth, 

 oblique at the base, cordate or subcordate, essentially glabrous or minutely pubescent be- 

 neath, especially in the axils of the prominent nerves when young : bracts decurrent 

 nearly to the base of the peduncles : sepals ovate-lanceolate to lanceolate, 6-8 mm. long, 

 acute, puberulent : petals 9-11 mm. long, pale yellow, obtuse : staminodia spatulate, neai-ly 

 as long as the petals : berries oval, about 1 cm. long, densely tomentulose. 



In woods. New Brunswick to the Assiniboine River, North Dakota, Georgia and Texas. Early 

 summer. 



2. Tilia austr^lis Small. A tree, becoming 20 m. tall. Leaf -blades relatively thin, 

 ovate to oval-ovate, 7-17 cm. long, abruptly acuminate, serrate with prominently gland- 

 tipped teeth, deep green above, glaucous beneath, essentially glabrous, cordate or nearly 

 truncate at the base : bracts relatively large, often 4 cm. wide, decurrent to the base of the 

 peduncle or near it, glaucous, glabrous : peduncle glabrous, the free portion 2-4 cm. long : 

 sepals narrowly ovate to ovate-lanceolate, 3.5-4 mm. long : petals 5.5-7 mm. long : stami- 

 nodia linear-spatulate, slightly shorter than the petals : berries globular. 



On wooded hillsides, Blount County, Alabama. Late spring and early summer. 



3. Tilia Florid^na Small. A tree, sometimes 9 m. tall, with a furrowed bark. Leaf- 

 blades thin, ovate or oval-ovate, 4-11 cm. long, abruptly short-acuminate, serrate with 

 conspicuously gland-tipped teeth, deep green above, glaucous beneath and with scattered 

 hairs when young, obliquely truncate or subcordate at the base : bracts relatively small, 

 mostly much less than 2 cm. wide, decurrent to within 0.5 or 1.5 cm. of the base of the 

 peduncle, somewhat pubescent : peduncle pubescent, the free portion 0.5-1.5 cm. long : 

 sepals lanceolate to linear-lanceolate, 3-3.5 mm. long : petals 4.5-5.5 mm. long : staminodia 

 nearly linear or linear-spatulate, slightly shorter than the petals : berries globular. 



In rich woods, Jackson County, Florida. Late spring and early summer. 



4. Tilia heterophylla Vent. A tree, reaching a maximum height of 30 m., with a 

 trunk diameter of about 1 m., the bark furrowed, its ridges flat. Leaf-blades varying from 

 orbicular-ovate to oblong-ovate, 10-20 cm. long, short-acuminate, serrate with more or less 

 appressed mucronate teeth, cordate or truncate at the oblique base, silvery or closely gray- 

 tomentulose beneath : bracts spatulate, decurrent to the base of the peduncle or nearly to 

 it, mostly abruptly narrowed at the base, thinly pubescent or glabrate : free portion of the 

 pediincle relatively long : sepals ovate-lanceolate to oblong-lanceolate, 6-8 mm. long, 

 acutish : petals 8-9 mm. long : staminodia oblong-lanceolate, about \ shorter than the 

 petals : berries globular, 7-9 mm. long. 



In rich woods, New York to Florida, Tennessee and Alabama. Late spring and early summer. 



5. Tilia eburnea Ashe. A tree, becoming 22 m. tall, the bark furrowed. Leaf-blades 

 thick, ovate to orbicular-ovate, 8-14 cm. long, abruptly acuminate at the apex, sharply 

 serrate, densely white-tomentose beneath, obliquely cordate or truncate at the base : bracts 

 nearly oblong to spatulate, decurrent to the base of the peduncle or nearly so, thinly pubes- 

 cent beneath : free portion of the peduncle short : somewhat shorter than that of f. hetero- 

 phylla: sepals ovate-lanceolate : petals 5-6 mm. long : staminodia spatulate : berries globu- 

 lar, sometimes spheroidal, 5-7 mm. long. 



In low woods or along streams, middle North Carolina to northern Georgia. Late spring and early 

 summer. 



6. Tilia Michavixii Nutt. A tree, sometimes fully 30 m. tall, with a broadly furrowed 

 bark. Leaf-blades thick, 7-22 cm. long, acuminate at the apex, serrate, silvery or gray- 

 tomentulose beneath, cordate or sometimes truncate at the usually very oblique base : bracts 

 spatulate, often elongated, decurrent to Avithin 1 or 3 cm. of the base of the peduncle, usually 

 tapering at the base, thinly pubescent beneath : free portion of the peduncle relatively long, 

 glabrous: sepals narrowly ovate to oblong-lanceolate, 4.5-6 mm. long: petals 6-9 mm. 

 long : staminodia spatulate, somewhat shorter than the petals : berries mostly oval, 7-11 

 mm. long. 



In woods, Pennsylvania and Ohio to Georgia and Alabama. Late spring and early summer. 



7. Tilia pub6scena Ait. A tree, becoming 14 m. tall, with a coarsely furrowed bark. 

 Leaf-blades thick and firm, broadly ovate to oblong-ovate, 8-17 cm. long, acute or abruptly 

 acuminate, more or less coarsely serrate, copiously brown or rusty pubescent beneath, 

 truncate or subcordate at the oblique base : bracts oblong to oblong-spatula te, decurrent to 

 the base of the peduncle, copiously pubescent beneath : peduncle pubescent : sepals lance- 

 olate, 3.5-4.5 mm. long: petals 6-7.5 mm. long : staminodia spatulate, about k as long as 

 the petals : berries globular. 



In low or rich woods, along or near the coast, Virginia to Florida and Louisiana. Late spring and 

 early summer. 



