UMBELLIFER.E. 147 



1. H. prolifera, Kell. Herbage light green and flaccid: leaves about 

 1 in. broad, peltate, emarginate at base, simply crenate, on petioles 14 

 in. long: peduncles equalling or exceeding the leaves: fl. in 1 4 whorls, 

 each 4 12-fiowered, with many bractlets; pedicels 16 lines long: fr. 1 

 line wide, emarginate at base; ribs 2 on each side, prominent. Said to 

 occur near San Francisco; common in the Suisun marshes. June Aug. 



2. H. ranunculoides, L. Herbage dark green, fleshy: leaves 12 in. 

 broad, round reniform, 3 7 -clef I, the lobes crenate; petioles 210 in. 

 long; peduncles much shorter (^ 3 in.), reflexed in fruit: fl. 5 10 in a 

 capitate umbel: fr. very shortly pedicellate, 1 1^ lines broad, with 

 thickened but scarcely angled margins, rather obscurely nerved on each 

 side, longer than the pedicels. In shallow ponds, margin of lakes, etc., 

 along the seaboard. 



2. BOWLESIA, Ruiz & Pavon. Slender very flaccid herbs, with 

 sparse stellate pubescence, and opposite simple leaves with scarious 

 lacerate stipules. Flowers minute, white, in simple few-flowered umbels 

 on axillary peduncles. Calyx-teeth rather prominent. Petals elliptical, 

 obtusish. Fruit broadly ovate, with narrow commissure, turgid, becom- 

 ing depressed on the back, without ribs or oil- tubes. 



1. B. lob at a, R & P. Annual, the slender stems more or less dicho- 

 tomous, 2 in. to 1 ft. long: leaves round-reniform or cordate, % 1^ in. 

 broad, shorter than the slender petioles, deeply 5-lobed; lobes acutish, 

 entire or few-toothed : umbels short-peduncled, 1 4-flowered: fr. 1 line 

 long, sessile or nearly so, pubescent, the inflated calyx not adherent to 

 the carpels. Among rocks, under trees, etc., on hillsides. April, May. 



3. ERYNCrlUM, Nicander (BUTTON SNAKEROOT). Perennials with 

 rigid coriaceous spinosely toothed or divided leaves, and white or blue 

 flowers sessile in dense heads which are encircled by a series of bracts 

 forming an involucre; each flower also subtended by a rigid bract. 

 Calyx-teeth manifest, rigid, persistent. Fruit ovoid or obovoid, scarcely 

 compressed, covered with hyaline scales or vesicles; ribs obsolete; oil- 

 tubes 0; carpels and seeds semiterete. 



1. E. armatum, C. & K. Diffusely branching,! ft. high or more: 

 radical leaves oblanceolate, serrately or spinosely dentate or incised, 

 attenuate to a margined petiole; cauline narrower, sessile: heads pedun- 

 cled, globose, % in. thick; bracts of involucre triangular-lanceolate, 

 entire, thick-margined, 1 in. long and much exceeding the head; bracllels 

 similar and as prominent: fr. with lanceolate -acuminate calyx-lobes 

 longer than the styles. Common in low ground. 



2. E. Vaseyi, C. & B. Smaller, branching above: leaves oblanceo- 

 late, irregularly spinose-serrate, attenuate at base: involucral bracts 



