KEY TO FAMILIES xxv 



n. Plants not fleshy 



(m) Ovary many-celled 

 r. Stamen filaments united into a 



tube Malvaceae 31 



s. Stamen filaments not united 

 into a tube 

 (r) Aquatic plants with simple 



floating leaves Nymphaeaceae 9 



(s) Land plants with pinnate 



leaves Zygophyllaceae 41 



(n) Ovary 5-celled 

 r. Ovary superior 



(r) Leaves simple or none 

 h. Leaves none; plants not 



green Monotropaceae 82 



i. Leaves present ; plants 

 green. 



(h) Leaves evergreen; 



petals persistent Pirolaceae 78 



(i) Leaves not evergreen; 

 petals falling in a 

 few hours Linaceae 40 



(s) Leaves deeply cut or com- 

 pound 

 h. Leaves deeply cut Geraniaceae 37 



i. Leaves of 3 leaflets Oxalidaceae 39 



s. Ovary inferior Araliaceae 222 



(o) Ovary 1-4-celled 

 r. Ovary 2-4-celled 

 (r) Ovary superior 

 h. Leaves simple 



(h) Ovary 2-celled Saxifragaceae 191 



(i) Ovary 3-celled Euphorbiaceae 34 



i. Leaves compound 



(h) Leaves of 3 leaflets Menyanthaceae 99 

 (i) Leaves pinnate Limnanthaceae 37 



(s) Ovary inferior 

 h. Calyx tube not grown to 

 the ovary ; capsule 

 many-seeded Lythraceae 199 



