868 AMMIACEAE 



sessile. Involucres wanting. Involucels of a few bracts. Sepals prominent. Petals 

 yellow. Disk flat. Fruit somewhat elongated, laterally flattened : carpels with 5 slender 

 wingless ribs and an oil-tube in each interval and under each rib. Seeds angled. The 

 plants flower in spring and summer. 



Basal leaves with merely toothed cordate "blades. 1. Z. cordata. 



Basal leaves with 2-3-ternately compound blades. 



Foliage light green : rays of the umbel stiff, ascending : fruit 4 mm. long. 2. Z. aurea. 



Foliage dark green : rays of the umbel filiform, irregularly spreading : fruit less than 3 



mm. long. 3. Z. Bebbii. 



1. Zizia cordata (Walt.) DC. Stems 4-10 dm. tall, mostly branched, pale green : 

 leaf-blades various, those of the basal leaves ovate or suborbicular, 3-10 cm. long, crenate, 

 deeply cordate, those of the stem-leaves mostly 3-foliolate or sometimes 5-foliolate ; seg- 

 ments crenate or serrate-crenate : umbels 2-6 cm. broad : rays 7-16, ascending, 1-5 cm. 

 long : corolla yellow, about 2 mm. broad : fruit ovate or oval, 3 mm. long, 10-ribbed. 



In woods and copses, Connecticut to the Northwest Territory, Georgia, Missouri and Oregon, 



2. Zizia aurea (L.) Koch. Stems 3-8 dm. tall, simple or branched above : leaf- 

 blades once to thrice ternately compound, those of the basal and lower stem-leaves long-pe- 

 tioled, thosej of the upper stem-leaves once ternate, on short winged petioles ; segments 

 oblong-ovate to lanceolate, 2-8 cm. long, sharply serrate : umbel 3-6 cm. broad : rays 9-25, 

 stiff, ascending, unequal, 2-5 cm. long : corolla yellow, 3-3.5 mm. broad : fruit oblong, 

 about 4 mm. long. 



In meadows and swamps, New Brunswick to Ontario, Montana, Florida and Texas. 



3. Zizia B6bbii (Coult. & Kose) Britton. Stems often tufted, 1-6 dm. tall, simple 

 or branching, dark green : leaf-blades once to thrice ternately compound, the lower ones 

 long-petioled, the upper with winged'petioles : leaflets thickish, oval, oblong, elliptic or 

 lanceolate, 1-4 cm. long, serrate : umbels slender-peduncled, straggling : rays 2-12, filiform, 

 unequal, 2-8 mm. long, unequally spreading : fruit suborbicular or broader than high, 

 2-2. 5 mm. long. \Z. aurea var. Bebbii Coult. & Kose.] 



In woods on mountain slopes, Virginia and West Virginia to Georgia. 



20. CICUTA L. 



Perennial herbs, with tuberous roots. Leaves alternate : blades pinnately compound, 

 or decompound : leaflets toothed. Flowers in compound umbels. Involucres of few bracts 

 or wanting. Involucels of several small bracts. Sepals acute. Petals white, broad, the 

 tips inflexed. Fruit slightly laterally flattened : carpels with 5 corky ribs and an oil-tube in 

 each interval, and 2 in the inner face. Seeds nearly terete. WATER HEMLOCK. 



Fruit oval or ovoid, 4 mm. long, not constricted at the commissure. 1. C. maculata. 



Fruit orbicular, 2 mm. long, constricted at the commissure. 2. C. Curtissii. 



1. Cicuta maculata L. Tubers clustered, elongated. Stems 1-2 m. tall, glaucous 

 marked with purple ridges, at length branched throughout : leaf-blades ample, triangular 

 in outline, 1-6 dm. long, twice or thrice compound, the lower ones long-petioled, the 

 upper with short dilated involute petioles : leaf-segments lanceolate or elliptic-lanceolate, 

 2-14 cm. long, acuminate, coarsely serrate, their nerves impressed above, very prominent 

 beneath, ending in the notches : bracts subtending the compound umbels linear-subulate, 

 deciduous : rays numerous, very unequal : sepals triangular : petals white, about 1 mm. in 

 diameter, broader than long, apiculate and rolled in at the apex, short-clawed : fruit ovoid 

 or oval, 4 mm. long, not constricted at the commissure, the lateral ribs much the largest, 

 wedge-shaped in section and contiguous : oil -tubes large. 



In swamps and meadows, New Brunswick to Manitoba, Virginia and Texas. Summer. MUSQUASH 

 ROOT. 



2. Cicuta Curtissii Coult. & Rose. Resembling C. maculata, but with a stouter root- 

 stock, thicker and more reticulated leaf -segments : fruit orbicular, 2mm. long, constricted 

 at the commissure, the ribs apparently nearly equal, but the lateral ones largest, neither 

 wedge-shaped nor contiguous. 



In swamps and low grounds, Virginia to Florida and Louisiana. Summer and fall. 



21. DERINGA Adans. 



Perennial caulescent herbs. Leaves alternate : blades 3-foliolate : leaflets toothed, in- 

 cised or lobed. Flowers perfect, in irregular compound umbels. Involucres and involu- 

 cels wanting. Hypanthium truncate. Petals white. Disk with a conic stylopodium. 

 Fruit elongated, latterally flattened : carpels slightly 5-angled with low ribs, and an oil-tube 

 beneath each rib and in each interval. Seeds nearly terete. HONEWOBT. 



