DICOTYLEDONOUS PLANTS 161 
VI. THASPIUM, Nutt. 
Perennial herbs. Stem erect. Leaves 1-2, compound in 
threes. Umbels compound, involucre and involucels usually 
wanting. Flowers yellow or purple. Calyx-teeth small, 
acute. Fruit ovoid or oblong, somewhat laterally compressed ; 
earpels smooth, strongly ribbed, oil-tubes between the ribs.* 
1. T. barbinode, Nutt. Harry Mreapow Parsnip. Stem erect, 
branching above, downy at the nodes, 2-7 ft. high. Leaves petioled, 
slightly downy, leaflets mostly thin, ovate, toothed, incised or lobed 
toward the apex, entire toward the base. Umbels long-peduncled, 
few-rayed. Fruit oblong, lateral and central ribs strongly winged. 
Along streams.* 
-VIl. ZIZIA, Koch. 
Smooth perennials. Leaves generally as in Thaspium. 
Involucre wanting; involucels of small bractlets. Umbels 
compound. Flowers yellow. Calyx-teeth prominent. Fruit 
more or less ovoid, smooth, with thread-like ribs, oil-tubes 
large and solitary between the ribs and a little one in each 
rib ; the central fruit of each umbellet sessile. 
1. Z. aurea, Koch. Mrapow Parsnip, GOLDEN ALEXANDERS. 
Smooth, stem erect, 1-2 ft. high. Root-leaves mostly heart-shaped 
and serrate, stem-leaves usually once compound in threes. Flowers 
deep yellow. Fruit between globose and ovoid, about 2 in. long, all 
the ribs generally winged. Woods and thickets. 
Vill. PASTINACA, L. 
A tall, smooth biennial with a stout, grooved stem. Leaves 
pinnate. Flowers yellow, in large umbels, with hardly any 
involucre. Calyx-teeth wanting. Fruit oval, very flat, with 
a thin wing, oil-tubes single, running the whole length. 
1. P. sativa, L. Common Parsnip. Cultivated from Europe 
for its large, conical, sweet, and edible roots. Also introduced in 
waste places. 
IX, HERACLEUM, L. 
A stout perennial, with the very large leaves compound in 
threes. Umbels large, compound, with the involucels many- 
