19 
Perianth open, not tubular. 10 
Perianth tubular. 
Anthers opening by recurved valves. AtherospermACE.®. 
Anthers opening lengthwise. Myristicaceas. 
10. — Seeds with albumen. H 
Seeds without albumen. Embryo straight. 
Perianth two leaved. Casuarixaceae. 
Perianth many parted. Ceratophyllaceje. 
11. — Embryo curved around the albumen. 
ClIENOPODIACEAE. p. 284. 
Embryo straight, Moximiaceae. 
12. — Ovules numerous. Leaves pitcher like. Nepextiiaceae. 
Ovules few. 
Ovules ascending. Empetraceae. 
Ovules suspended. Euphorbiaceae. p. 293. 
13. — Flowers imperfect, some staminate, some pistillate. 15 
Flowers perfect, having both stamens and pistils. 
Carpels more than one, combined into a solid pistil. 14 
Carpel single. 
Stipules single. PETivERiACEiE. 
Stipules sheathing the stem. Poly'GOXACEAE. p. 287. 
14. — Leaves with round, transparent, solitary dots. Samtdace^e. 
Leaves without clots. 
Perianth regular, in a double row. Chaieletiaceae. 
Perianth irregular, in a single row. Ulmaceae. p. 296. f 
15. — Carpels more than one, combined into a solid pistil. 16 
Carpel solitary. 
Anther cells perpendicular to the filament. Stieaginaceas. 
Anther cells parallel to the filament. 
Sap watery. Urticaceae. p. 296. 
Sap milky. Artocarpaceae. 
16. — Flowers not in aments. Eupiiorbiace/E. p. 293. 
Flowers in aments. 
Seeds without an aril. Betulaceae. p. 306. 
Seeds with an aril. 
