2. H. Cánbyi, Coult. & Rose. _Umbels 3--9-flowered, generally proliferous; pedicels very short_, but distinct; _fruit about 2 lines broad_; carpels broader and more flattened than in the preceding, sharper margined, the dorsal and lateral ribs much more prominent; seed-section much narrower. (H. umbellata, var.? ambigua, _Gray_, Manual).--N. J. to Md. [+][+] _Fruit not notched; intermediate ribs not corky._ 3. H. verticillàta, Thunb. Umbels few-flowered, proliferous, forming an interrupted spike; pedicels very short or none; fruit 1½--2´´ broad; dorsal and lateral ribs very prominent. (H. interrupta, _Muhl._)--Mass. to Fla. [*][*] _Pericarp uniformly corky-thickened and ribs all filiform; leaves not peltate; peduncles much shorter than the petioles._ [+] _Fruit small, without secondary ribs or reticulations; involucre small or none._ 4. H. Americàna, L. Stems filiform, _branching and creeping; leaves thin_, round-reniform, _crenate-lobed_ and the lobes crenate, shining; few-flowered umbels _axillary and almost sessile_; fruit less than 1´´ broad; intermediate ribs prominent; no oil-bearing layer; seed-section broadly oval.--Common. (Addendum) Propagating by filiform tuberiferous stolons. 5. H. ranunculoìdes, L. f. _Usually floating; leaves thicker_, round-reniform, 3--7-cleft, the lobes crenate; _peduncles 1--3´ long, reflexed in fruit_; capitate umbel 5--10-flowered; fruit 1--1½´´ broad; ribs rather obscure; seed-section oblong.--E. Penn. to Fla., thence westward. [+][+] _Fruit larger (2--2½´´ broad), with prominent secondary ribs and reticulations; the 2--4-flowered umbel subtended by two conspicuous bracts._ 6. H. Asiática, L. Petioles and peduncles (1--2´ long) clustered on creeping stems or runners; leaves ovate-cordate, repand-toothed, thickish; seed-section narrowly oblong. (H. repanda, _Pers._)--Md. to Fla. and Tex. (Widely distributed in the tropics and southern hemisphere.) 35. ERÝNGIUM, Tourn. ERYNGO. Calyx-teeth prominent, rigid and persistent. Styles slender. Fruit ovate or obovate, covered with little hyaline scales or tubercles, with no ribs, and usually 5 slender oil-tubes on each carpel.--Chiefly perennials, with coriaceous, toothed, cut, or prickly leaves, and blue or white bracted flowers closely sessile in dense heads. (A name used by Dioscorides, of uncertain origin.) [*] _Stout, with parallel-veined elongated linear thick leaves._ 1. E. yuccæfòlium, Michx. (RATTLESNAKE-MASTER. BUTTON SNAKE-ROOT.) Branching above, 1--6° high; leaves rigid, tapering to a point (lower sometimes 2--3° long), the margins remotely bristly; heads ovate-globose (9´´ long), with ovate-lanceolate mostly entire cuspidate-tipped bracts shorter than the head, and similar bractlets.--Dry or damp soil, N. J. to Minn., south to Fla. and Tex. July--Sept. [*][*] _Tall and often stout; leaves thick, not parallel-veined._