EANTJNCULACEJE. 79 



GENERA. 



I. AQUILEGEiE. 



a. Flowers regular. 



1. Aquilegia T. — Flowers 5-meroiis. Calyx petaloid imbricate 

 deciduous. Petals 5, alternate with the sepals, usually calcarate. 

 Stamens 8—10 alternating 5-merous verticils ; anthers extrorse, 

 dehiscing by 2 clefts. Staminodes within these 10, in 2 alternating 

 verticils. Carpels 5, sessile free multiovulate. Follicles 5, poly- 

 spermous. Seeds albuminous, embryo minute. — Perennial herbs ; 

 leaves compound alternate ; flowers solitary terminal, or in cymes 

 {Europe, Asia, N. America). See p. 1. 



2. Xanthorhiza Lher. — Flowers 5-merous. Calyx petaloid im- 

 bricate deciduous. Petals 5, alternate with the sepals, unguiculate 

 gland-like dilated at the apex. Stamens in 1 — 3 alternating 5-merous 

 or in complete verticils. Anthers sublateral, dehiscing by 2 clefts. 

 Carpels 5 — 15 sessile free pauciovulate. Follicles often 1 -seeded by 

 abortion. — A shrub, leaves alternate pinnatisect ; flowers in few- 

 flowered racemose cymes (iV. America). See p. C. 



3. Nigella T. — Flowers 5-merous. Calyx petaloid imbricate 

 deciduous. Petals (staminodes ?) opposite the sepals (often in pairs), 

 bifid at the apex. Stamens spirally inserted ; anthers introrse, 

 dehiscing by 2 clefts. Carpels 2 — 1 5 (usually 5) connate at the base 

 (obliquely inserted) many ovuled, dehiscing internally at the apex 

 when ripe. — Annual herbs ; leaves alternate dissected, often forming 

 an involucre to the terminal flowers [Eurojje, JFest Asia). See p. 7. 



4. Helleborus T. — Calyx 5-or 6-merous imbricate persistent or 

 deciduous. Petals (staminodes ?) varying in number and position, 

 gland-like, rarely 0. Stamens spirally arranged ; anthers extrorse 

 or introrse, dehiscing longitudinally. Carpels 2-oo , free or cohering 

 at the base, sessile or stipitate, multiovulate, dehiscing as follicles 

 when ripe. — Perennial herbs, with palmate or pedate leaves. 



