22 American Midland Naturalist Monograph No. 7 



23. Petals and stamens inserted on 

 the calyx; branches usually 



more or less angled 



75. Lythraceae 



22. Styles 2; petals 5; sepals 5, re- 

 flexed; stamens 10; leaves chief- 

 ly basal 62. Saxifragaceae 



21. Flowers irregular; anthers opening by 



terminal pores 42. Polygalaceae 



7. Petals united (the corolla sympetalous). 

 25. Corolla regular (actinomorphic) . 



26. Flowers large (1.5-6 cm long) ; fruit a capsule. 



27. Plants with milky juice, often climbing; capsules few- 

 seeded 105. Convolvulaceae 



27. Plants with watery juice, never climbing; capsules many- 



seeded 107. Solan ACE AE 



26. Flowers smaller. 



28. Plants with milky juice ; fruit of 1 or 2 large pods, the 



seeds with a tuft of silky hairs. 

 29. Flowers in umbels; filaments united into a tube en- 

 closing the pistil 100. Asclepiadaceae 



29. Flowers in cymes, purplish blue; stamens free 



Amsonia in 99. .\pocynaceae 



28. Plants with watery juice. 



30. Fruit of 4 (or sometimes fewer) nutlets; plants rough- 



hairy, often bristly, or glabrous and with blue 



flowers 1 15. Boraginaceae 



30. Fruit a capsule or berry. 



31. Flowers blue; fruit a capsule. 



32. Ovary superior; styles 2 



106. Hydrophyllaceae 



32. Ovary inferior: style 1 121. Campanulaceae 



31. Flowers not blue. 



33. Style 3-cleft 104. Polemoniaceae 



33. Style not 3-cleft. 



34. Flowers in umbels 100. Asclepiadaceae 



34. Flowers not in umbels. 



35. Plants climbing or twining; flowers 

 purple (rarely white) in small 



cymes; berries ovoid, red So- 



lanum dulcamara in 107. Solanaceae 



35. Plants not climbing or twining. 



36. Flowers white or pink or yellow; 

 fruit a capsule ; calyx not en- 

 larged in fruit ...97. Primulaceae 



36. Flowers yellowish or whitish, often 

 with a dark center; fruit a berry, 

 enclosed by the 5-lobed, 10- 

 ribbed, often 5-10-angled, reticu- 

 lated, inflated calyx 



Physalis in 107. Solanaceae 



25. Corolla irregular ( zygomorphic ) . 

 37. Ovary superior. 



