12 American Midland Naturalist Monograph No. 7 



34. Petals and sepals 4 or more, or ab- 

 sent; or the sepals united, some- 

 times only 2. 

 35. Sepals 2, caducous (falling as 

 the flower opens) ; plants with 

 milky or yellowish juice; sta- 

 mens numerous, hypogynous; 



fruit a capsule 



13. Papaveraceae 



35. Sepals 4 or 5; plants with 

 watery juice. 

 36. Petals and sepals each 4, 

 fruit a pod. 

 37. Leaves trifoliolate; sta- 

 mens 6 or more, ex- 



serted 



17. Capparidaceae 



37. Leaves not trifoliolate; 



stamens 6, four long 



and two short 



18. Cruciferae 



36. Petals 5 or none; sepals 

 usually 5, sometimes 4; 

 fruit an achene or follicle, 

 or rarely a berry. 

 38. Stamens and petals hy- 

 pogynous; sepals free 

 3. Ranunculaceae 



38. Stamens and petals pe- 



rigynous; sepals united 

 at base ...53. Rosaceae 



Section 3. Herbs Without Leafy Stems; Leaves Simple 



1. Leaves either pitcher-like or covered with glandular appendages; petals 5; 

 fruit a capsule; insectivorous plants growing in bogs. 

 2. Leaves large, pitcher-like; flower solitary, nodding 21. Sarraceniaceae 



2. Leaves small, covered with glandular appendages; flowers in a raceme 



15. Droserageae 



1. Leaves not as above; plants not insectivorous. 



3. Flowers sessile in dense heads, or in spikes. 

 4. Flowers in heads. 



5. Leaves parallel-veined, grass-like, stiff, flat, linear, twisted; flowers 



yellow, perfect; capsule many-seeded 132. Xyridaceae 



5. Leaves net-veined, or rarely apparently only 1-veined. 



6. Involucre of 4 white bracts; leaves whorled at the summit of the 

 stem; calyx minutely 4-toothed ; petals 4; stamens 4; drupe red 

 Cornus canadensis in 90. Cornaceae 



6. Involucral bracts otherwise; calyx in the form of a pappus; sta- 

 mens 5, inserted on the corolla, their anthers united into a 

 tube; fruit an achene 125. Compositae 



4. Flowers in spikes (or on a spadix). 



