ORDER CXV. — AMENTACEiE. 509 



Genus VIII.— OS'TRYA. Mich. 10—12. 

 (From the Greek ostruos, a scale.) 



Monoecious. Sterile florets; nmeut cyliiKlrical ; scales 1- 

 flovvered ; tilaments branched. Fertile flurets ; ament iiakoil. 

 Capsicles inflated, imbricate, 1-seeded at the base. 



1. 0. Virgin'ica, (Willd.) A small tree, with very compact, hard 

 wood. Leaves ovate-oblong, cordate at the base, alternate, unequally 

 serrate. A?nent oblong-ovate, erect, with inflated capsules, l-seede<l. — 

 ^ . May. In woods. 20 — 30 feet. Iron-icood. 



Sub-order IV.— PLATANA'CE^. {Plane Tribe) 



Genus IX.— PL AT' ANUS. L. 19—12. 

 (From the Gtet^'k platus, ample, in allusion to its foliage.) 



Monoecious. Sterile florets ; ament globose. Stamens nu- 

 merous, intermixed with linear scales. Fertile florets; scales 

 spatulate. Stigma recurved. Seed clavate. 



1. P. occidenta'lis, (L.) a lai-ge tree, with nearly white branches 

 with soft wood. Leaves 5-angled, obscurely toothed, pubescent lieneath. 

 Aments axillary, on long peduncles. ^SVecZ forming a compact head. — 

 ^ . May. Banks of streams. 60—70 feet. 



Button-xL'ood or Sycamore. 



Genus X.— LIQUIDAM'BAll. L. 19—12. 

 (From liquidus, liquid, and amher, amber, in allusion to the exudation from the trees.) 



Monoecious. Sterile florets ; ament conical, with a 4-leaved 

 involucre ; perianth none. Stamens numerous. Fertile fl(trets ; 

 ament globose ; perianth 2-leaved, urceolate, 2-flowered. Sfi/les 

 2. Capsules 2, 1 -celled, many-seeded. 



1. L. styraciflu'a, (L.) A large tree. Leaves alternate, palmately 

 lobed ; lobes acuminate, serrate. Sterile ament terminating the l)ranch- 

 es. Fertile ament near the base of the sterile. — h. May. Damp 

 soils. 70—80 feet. Sweet Gnui. 



Sub-order V.— CUPULIF'ER^. (JVut Tribe.) 



Genus XL— QUER'CUS. L. 19—12. 

 (From the Celtic quer, fine, and cuez, a tree.) 



Monoecious. Sterile florets ; ament loose ; perianth mo.stly 

 6 — 8-cleft. Stamens 5 — 10. Fertile florets; capsule cu{> 

 shaped, scaly ; perianth C -lobed. Ovary 3-celled, 2 of them 

 abortive. Style 1. Stigmas 3. Acorn 1-celled, 1-sceded. 



a. Fructification biennial. Leaves usually setaceously mucronat% entire. 



1. Q. phel'los, (L.) A miildle-sized tree, slender and straight 



Leaves deciduous, linear-lanceolate, tapering at both ends, glabrous, 



