xxxii 



25a. Juice milky 16, in COMPOSITAE, p. 115, 



25b. Juice not milky 26. 



26a. Aquatic or mud plants, with large entire leaves 1 4 dm. 

 wide NYMPHAEACEAE, p. 35. 



26b. Land plants, with smaller or lobed leaves 27. 



27a. Flower-stalk scaly 110, in COMPOSITAE, p. 122. 



27b. Flower-stalk bare or with 1 to 2 minute bracts 28. 



28a. Flowers regular 10, in RANUNCULACEAE, p. 36. 



28b. Flowers irregular, with a spur 3a, in TIOLACEAE, p. 75. 



29a. Flowers obviously irregular, with a spur 30. 

 29b. Flowers regular or nearly so, without a spur 31. 



30a. Leaves sessile or nearly so; stamens 2 



LENTIBULARIACEAE, p. 105. 

 30b. Leaves petioled; stamens 5 TIOLACEAE, p. 75. 



31a. Flowers 3 mm. wide or smaller; leaves thread-like 



16a, in SCROPHULARIACEAE, p. 103. 

 31b. Flowers 6 mm. wide or larger 32. 



32a. Ovary 1 33. 



32b. Ovaries numerous 37. 



33a. Leaves lobed or cleft 34. 

 33b. Leaves entire or toothed 35. 



34a. Leaves deeply 2-cleft; stamens 8 



3a, in BERBERIDACEAE, p. 40. 

 34b. Leaf 1, palmately lobed; stamens numerous 



la, in PAPAVERACEAE, p. 41. 



35a. Flowers dull red ARISTOLOCHIACEAE, p. 25. 



35b. Flowers white or pinkish 36. 



36a. Leaves entire; stamens with good anthers 5 



13, in SAXIFRAGACEAE, p. 50. 

 36b. Leaves minutely toothed; stamens 8 10 



14a. in ERICACEAE, p. 85. 



37a. Leaves lobed or divided RANU1VCULACEAE, p. 35. 



S7b. Leaves crenate or toothed 64a, in ROSACEAE, p. 56. 



38 



38a. Flowers of the composite type, with several or many small 

 flowerets closely aggregated into a dense head surrounded by 

 a calyx-like involucre of small bracts 



10, in COMPOSITAE, p. 114. 



38a. Flowers separate; variously clustered, but never crowded 

 into involucred heads 39. 



