WOOTON AND STANDLEY—FLORA OF NEW MEXICO. 17 
Ovary superior. 
Stamens inserted on the margin of a disk or hypanthium (perigynous or hypo- 
gynous). 
Stamens as many as the petals and opposite them. 
Styles and upper part of the ovaries distinct; ovules and seeds many. 
(Saxifragaceae) 27. ROSALES (p. 291). 
Styles united; ovules and seeds solitary or2..32. RHAMNALES (p. 412). 
Stamens as many as the petals and alternate with them or more. 
Styles distinct .............-. (Saxifragaceae) 27. ROSALES (p. 291). 
Styles united. 
Hypanthium cup-shaped or campanulate; disk obsolete or incon- 
spicuous......-.---....2. 22 eee eee eee 37. MYRTALES (p. 459). 
Hypanthium flat or obsolete; disk fleshy. 
Plants with secreting glands in the bark. 
(Rutaceae) 28. GERANIALES (p. 379). 
Plants without secreting glands in the bark. 
81. SAPINDALES (p. 405). 
Stamens inserted at the base of the ovary or receptacle. 
Stamens numerous. 
Sepals valvate; filaments united............. 33. MALVALES (p. 416), 
Sepals imbricated; filaments various...... 26. PAPAVERALES (p. 260). 
Stamens few, not over twice as many as the petals, 
Stamens as many as the petals and opposite them. 
Anther sacs opening by hinged valves, 
(Berberidaceae) 25. RANALES (p. 243). 
Anther sacs opening by slits. 
Flowers moneecious............+---- 30. EUPHORBIALES (p. 392). 
Flowers perfect. 
Ovules and seeds several or many; embryo coiled. 
(Portulacaceae) 24, CHENOPODIALES (p. 198). 
Ovules and seeds solitary; embryo straight. 
(Plumbaginaceae) 40, PRIMULALES (p. 490). 
Stamens as many as the petals and alternate with them or more, some- 
times twice as many. 
Stamens 6; petals 4; sepals 2 or 4. 
(Families of) 26. PAPAVERALES (p. 260). 
Stamens, petals, and sepals of the same number, or stamens more than 
the sepals or petals, then usually twice as many. 
Ovary 1-celled. 
Ovules and seeds on basal or central placente. 
(Families of) 24, CHENOPODIALES (p. 198). 
Ovules and seeds on parietal placente. 
Stamens with united filaments (no staminodia). 
33. MALVALES (p. 416). 
Stamens with distinct filaments. 
Staminodia present.(Parnassiaceae) 27. ROSALES (p. 291). 
Staminodia wanting. 
(Families of) 34, HYPERICALES (p. 427). 
Ovary several-celled. 
Stamens adnate to the gynecium. 
(Asclepiadaceae) 44. ASCLEPIADALES (p. 503). 
Stamens not adnate to the gyneecium. 
Filaments wholly or partly united. 
Anthers opening by long slits. 
(Families of) 28. GERANIALES (p. 379). 
52576°—15——2 
