50 American Midland Naturalist Monograph No. 7 



I. Magnolia L. — Cucumber Tree 



M. acuminata L. Woods, s. 111., as far north as Jackson, Johnson, 

 and Pope counties. May. 



2. Liriodendron L. — Tulip Tree 



L. tulipifera L. Woods, local; s. 111., extending northeastward to 

 Vermilion Co. May. 



2. Annonaceae R.Br. — Custard-apple Family 



1. Asimina Adans. — Pawpaw 



A. triloba (L.) Dunal. Woods, nearly throughout 111., extending 

 northward to Cook and Lee counties. Apr. -May. 



3. Ranunculaceae Juss. — Buttercup Family 

 I. Flowers yellow. 



2. Petals none; sepals petal-like, yellow, deciduous; leaves crenate; carpels 



several-ovuled, becoming follicles 1. Caltha 



2. Petals present; sepals green; carpels 1-ovuled, becoming achenes 



9. Ranunculus 



1. Flowers not wholly yellow. 



3. Flowers white to pink. 



4. Stems climbing; leaves opposite; flowers in panicles 16. Clematis 



4. Stems not climbing; leaves not opposite. 



5. Flowers zygomorphic, spurred; leaves palmately divided or cleft; 



inflorescence a raceme 7. Delphinium 



5. Flowers actinomorphic, spurless. 



6. Aquatic plants with finely dissected leaves; sepals 5, green; petals 



5, white; carpels 1-ovuled, becoming achenes 9. Ranunculus 



6. Not aquatic, mostly woodland plants. 



7. Flowers racemose; petals small, stamen-like or none; leaves 

 ternately compound. 

 8. Racemes simple, short; fruit red or white, berry-like, 

 poisonous 5. Actaea 



8. Racemes paniculate, elongate: fruit a follicle 6. Cimicifuga 



7. Flowers solitary or in pairs, or 3 or 4 in an umbel, not 



racemose. 



9. Flowers with an involucre of 3 sepal-like bracts immediately 



beneath the calyx; leaves 3-lobed 14. Hepatica 



9. Flowers without an involucre, or the involucre similar to the 

 leaves, and remote from the flowers. 

 10. Sepals 3, petaloid, evanescent; petals none; carpels 2- 

 ovuled, becoming berries; leaves reniform, palmately 



lobed 2. Hydrastis 



10. Sepals 5 or more, petal-like; petals none; fruit of achenes 

 or follicles. 



II. Leaves palmately lobed or cleft, the segments usually 



sessile; fruit of achenes; plants with a rhizome or 



caudex 12. Anemone 



1 1 . Leaves ternately compound, the leaflets stalked. 



