MONOECIA.— POLYANDRIA. 32' 



HEXANDRIA. 



Ao. ZIZANIA. sterile fl. Cal. 0. Cor. 2-valved 

 subuvned. fertile fl. Cal. 0. Cor. 2-valved. 

 cucullate, awned. Style 2-parted. Seed 1, in- 

 vested by the corolla. 



5*6. HYDROCHLOA. sterile fl. Cal. 0. Cor. 2- 

 valved, awnless. fertile fl. Cat. 0. Cor. 2- 

 valved, awnless. Stig. 2, very long. Seed J 

 reniform. 



POLYANDRIA. 



547. CERATOPMYLLUM. sterile fl. Cal. many- 

 parted. Cor. 0. Stain. 16 — 20; anth. tricus- 

 pidate. fertile fl. Cal. many-parted. Cor. 

 0. Stig. nearly sessile, oblique. Nut 1 -seeded. 



518. MYRIOPHYLLUM. sterile fl. Cal. 4-cleft. 

 Petals 4, caducous. Stam. 4, 6, or 8. fertile 

 fl. Cal. 4-leaved. Petals 4. Stig. 4, pubescent ; 

 styles 0. Nuts 4, subglobose, 1 -seeded. 



549. SAGITTARIA. sterile fl. Cal. 3-leaved. 



Pet. 3. Stam. definite, fertile fl. Cal. 3- 

 leaved. Pet. 3. Germens numerous. Peri- 

 carps aggregated, 1 -seeded, not opening. 



550. QUERCUS. sterile fl. in a loose ament. Cal. 



mostly 5-rleft. Cor. 0. Stam. 5 — 10. fer- 

 tile fl. Invohicrum cup-shaped, scaly. Cal. 

 incorporated with the germen, 6-lobed. Germen 

 3-celled; 2 of the cells abortive. Style 1 ; stig. 

 3-5. Nut (acnrn) 1-celled, coriaceous, 1 seed- 

 ed, surrounded at the base by the enlarged 

 cup-shaped involucrum. 



551. CORYLUS. sterile fl. in a cylindrical ament, 



itfl scales 3-cleft. Perianth 0. Stam. 8 ; anth. 

 1-celled. FERTILE fl. Cal. obsolete. Germ. 

 several ; stig. 2. Nut ov;ite, surrounded with 

 the enlarged coriaceous and scaly involucrum. 

 FAGUS. sterile fl. in a globose ament. Cal, 

 5— G-cleft, campanulate. Stam. 5 — 12. FEB 



ri.. ( 2. Involucrum 4-lobed, prickly. 



single, i—5-ckft. Styles 3. Nut 1 -seeded, in 



led in the enlarged echinate involucrum. 



