ORDER CXV. AMENTACEiE. 511 



Var. (a) Q. tri'loba, (L.) Leaves cuneate, nearly equally 3-lobed at 

 the summit, mucronate. 



Var. (b) Q. pagod^efo'lia, (Ell.) Leaves oblong, many-lobed, on 

 rather long petioles ; lobes simple, mucronate. 



13. Q. ilicifo'lia, (Van.) A small shrub. Leaves cuneate, on long 

 petioles, obovate, 3 — 5-lobed, tomentose beneath. Fruit abundant. 

 Acorn ovate, in a shallow cup. — T ? . April — May. Poor soils. 3 — 8 ft. 



c. Fructification annual. Leaves unawned. 



14. Q. obtusilo'ba, (Mich.) A middle-sized tree, with irregular 

 branches. Leaves oblong, sinuate, on short petioles, generally 5 lobed, 

 the upper ones dilated, pubescent beneath. Acorn oblong, in a hemi- 

 spherical cup. — t> . April. In stony, clay soils. 30 — 40 feet. 



Post Oak. 



15. Q. lyra'ta, (Walt.) A large tree. Leaves long, irregularly ly- 

 rate, the lobes oblong, nearly acute, the upper ones dilated, glabrous. 

 Acorn nearly globular, almost entirely inclosed in the cup. — ^ . April. 

 In swamps. 60 — 70 feet. Over-cup Oak. 



16. Q. al'ba, (L.) A large tree. Leaves oblong, pinnatifid, sinuate, 

 pubescent beneath, on short petioles. Lobes oblong, obtuse. Fruit 

 large, usually in pairs. Acorn ovate, in a deep cup. — ^. Apiil. 

 Rich soils. 70—80 feet. White Oak. 



17. Q. pri'nus, (L.) A large tree, with a long trunk without branches. 

 Leaves large, obovate, or oblong lanceolate, obtusely toothed, slightly 

 pubescent beneath. Fruit abundant. Acorn large, in a hemispherical 

 cup. — *> . April. Common. 70 — 80 feet. Swamp-chestnut Oak. 



18. Q. Michaux'ii, (Nutt.) A large tree. Leaves obovate, unequally 

 toothed, sinuate, obtuse at the base, tomentose beneath. Fruit usually 

 in pairs. Acorn large, ovate. — ^ . April. Rich soils. 60 — 80 feet. 



19. Q. monta'na, (Willd.) A large tree. Leaves obovate, acute, to- 

 mentose beneath, coarsely toothed, teeth indurated at the point. Acorn 

 ovate, in a hemispherical cup. — ^ . April. In rocky places near the 

 mountains. 30 — 50 feet. 



20. Q. Casta'nea, (Muhl.) A large tree. Leaves oblong-lanceolate, 

 on long petioles, tomentose beneath, acuminate, coarsely-toothed, teeth 

 with indurated points. Acorn ovate, in a hemispherical cup. — ^. 

 April — May. In rich, damp soils. 60 — 70 feet. Chestnut Oak. 



21. Q. ciiin'quapin, (Mich.) A small shrub, with a smooth, slender 

 stem. Leaves oblong-lanceolate, on short petioles, coarsely toothed, 

 glabrous when mature. Acorn ovate, in a hemispherical cup. — ^ . 

 April — May. Near the mountains. 3 — 4 feet. 



Genus XII— CASTA'NEA. 19—12. 

 (Castanea, a town In Thessaly.) 



Monoecious. Sterile florets ; anient naked, long, cylindrical ; 

 perianth 6-lobed. Stamens 5 — 20. Fertile florets 3, within a 

 muricated involucre ; perianth 5 — 6-lobed. Styles 6. Seed 

 1 — 3, inclosed by the involucre. 



1. C. ves'ca, (L.) A large tree, generally with an erect trunk and 



