156 UMBELLIFEllJE. (PARSLEY FAMILY.) 



Var. ftpteruiii. Fruit with strong and sharp ribs in place of wings. 

 (Smyrnium aureum, L. Zizia aurea, Koch.) With the winged form. 



4. T. fri foil aili ill. Root-leaves or some of them round and heart-shaped; 

 stem-leaves simply ternate or quinate, or 3-parted ; the divisions or leaflets ovate-lance- 

 olate or roundish, mostly abrupt or heart-shaped at the base, crenately toothed; 

 flowers deep yellow ; fruit globose-ovoid, with 1 J winged ridges. Rocky thickets, 

 Vermont to Wisconsin, and southward ; rare eastward. June. 



Var. atropiirplireiim, Torr. & Gr. Petals deep dark-purple. (Thap- 

 sia trifoliata, L. Smyrnium cordatum, Walt. Thaspium atropurpureum, Nutt.) 

 From New York westward and southward. 



Var. apteru in. Petals yellow : fruit with sharp ribs in place of wings. 

 (Zizia, cordata, Koch, Torr.) With the preceding form. 



17. ZIZIA, DC. partly. (ZiziA TjENfDiA, Torr. & Gr.) 



Calyx-teeth obsolete. Fruit ovoid-oblong, contracted at the junction of the 

 carpels so as to become twin, the cross-section of each seed nearly orbicular : 

 carpels somewhat fleshy when fresh, with 5 slender ribs (which are more con- 

 spicuous when dry) : oil-tubes 3 in each interval and 4 on the inner face. A 

 perennial smooth and glaucous slender herb (2 -3 high), with 2 - 3-ternatoly 

 compound leaves, the leaflets with entire margins ; umbels with long and slen- 

 der rays, no involucre, and hardly any involucels. Flowers yellow. (Named 

 for /. B. Ziz, a Rhenish botanist.) 



1. Z. integerrima, DC. Rocky hill-sides ; not rare. May, June. 



18. BUPLiElTRUIJI, Tourn. THOROUGH-WAX. 



Calyx-teeth obsolete. Fruit ovate-oblong, flattened laterally or somewhat 

 twin, the carpels 5-ribbed, with or without oil-tubes. Plants with simple entire 

 leaves and yellow flowers. (Name from /3oCff, an ox, and irXevpov, a rib ; it is 

 uncertain why so called,) 



1. B. KOTUXDIF6LIUM, L. Leaves broadly ovate, perfoliate ; involucre 

 none; involucels of 5 large ovate leaflets. Fields, New York, Penn., and Vir- 

 ginia; rare. (Adv. from Eu.) 



19. DISCOPL.EIJRA, DC. MOCK BISHOP-WEED. 



Calyx-teeth awl-shaped. Fruit ovoid ; the carpels each with 3 strong ribs on 

 the back, and 2 broad lateral ones united with a thickened corky margin : inter- 

 vals with single oil-tubes. Smooth and slender branched annuals, with the 

 leaves finely dissected into bristle-form divisions, and white flowers. Involucre 

 and involucels conspicuous. (Name from StWos, a disk, and rrXevpov, a rib.) 



1. I>. capillacea, DC. Umbel few-rayed; leaflets of the involucre 

 3 - 5-cleft ; involucels longer than the umbellets ; fruit ovate in outline. 

 Brackish swamps, Massachusetts to Virginia, and southward. July -Oct. 



2. D. Nllttallii, DC. Umbel many-rayed ; leaflets of the involucre 

 mostly entire and shorter; fruit globular. Wet prairies, Kentucky and south 

 ward. 



