676 FLOKA. 



10. Bl'FORA Hoffm. 



Glabrous annuals, with dissected leaves and few-rayed umbels of white flowers. 

 Involucre and involucels of few small bracts. Fruit didymous, laterally flattened, 

 with globose glabrous hard carpels. Carpels with 4 Aliform secondary ribs. Stylo- 

 podium conic. Styles recurved. Oil-tubes none. [Latin, referring to the didy- 

 mous fruit.] About 4 species, natives of N. Am. and Europe. 



1. Bifora Americana (DC.) A. Gray. American Bifora. Slender, 

 roughish above, 2-4 dm. high. Ultimate leaf-segments narrowly linear, acutish. 

 Rays 5-8, 2.5 cm. long or less; pedicels 1-3 mm. long; carpels about 2 mm. in 

 diameter. Mo. (according to Drude); Ark. to Tex. and N. Mex. April-May. 



Bifora rddians Bieb., has been collected in waste places and ballast, in R. I. and 

 Penn. It differs from the preceding in its larger wrinkled fruit. 



11. APIASTRUM Nutt. 



Annual glabrous much branched herbs, with petioled finely dissected leaves, the 

 leaf-segments linear or filiform. Flowers very small, white, in compound unequal- 

 rayed umbels. Involucre none; involucels of a few small bracts, or none. Calyx- 

 teeth obsolete. Fruit ovate, or suborbicular, laterally flattened, tubercled, not 

 ribbed; pericarp thin; oil-tubes few, not clustered, 2 on the commissural side. 

 Seed-face concave. Stylopodium small. [Greek, false celery.] Two species, the 

 following, and one in Cal. 



1. Apiastrum patens (Nutt.) Coult. & Rose. Spreading Apiastrum. (I. F. 

 f. 2672. ) Erect, 3-6 dm. high, divergently branched above. Stem-leaves short- 

 petioled, biternately dissected; umbels terminal, or axillary, 1-4 cm. broad; rays 

 6-12 mm. long; pedicels 3-4 mm. long in fruit; fruit ovate, slightly more than 



1 mm. long, more or less tuberculate, usually densely so. Neb. and Mo. to Tex. 

 and N. Mex. June. 



12. ERIGENIA Nutt. 



Low glabrous nearly acaulescent perennial herbs, arising from a deep tuber, 

 with ternately decompound leaves, usually a single-leaved involucre, and small 

 umbels of white flowers. Calyx-teeth obsolete. Petals flat, entire. Fruit nearly 

 orbicular, notched at both ends, glabrous. Carpels incurved at top and bottom, 

 with 5 slender ribs and 1-3 small oil-tubes in the intervals. [Greek, spring- 

 born.] A monotypic genus. 



1. Erigenia bulbosa (Michx.) Nutt. Harbinger of Spring. (I. F. f. 2709.) 

 Stem scapose, 0.7-2.5 dm. high. Basal leaves 2-4, ternately divided into thin 

 oblong obtuse segments, the involucral one similar, smaller; petioles much dilated 

 at the base; umbels mostly compound, of 1-4 slender rays; involucels spatulate 

 or sometimes foliaceous; pedicels 2-5 mm. long in fruit; fruit about 2 mm. long 

 and 3 mm. broad. Ont. to D. C, Ala., Minn, and Kans. Feb. -April. 



13. conIum l. 



Tall biennial glabrous herbs, with spotted stems, pinnately decompound leaves, 

 and small white flowers in compound many-rayed umbels. Involucre and involu- 

 cels of ovate acuminate bracts. Calyx-teeth obsolete; petals obcordate, or entire 

 with a short inflexed point; fruit broadly ovate, glabrous, somewhat flattened later- 

 ally. Carpels strongly wavy-ribbed; large oil tubes none, but a layer of oil- 

 secreting tissue next the deeply concave seed. [Greek, hemlock.] Two species, 

 one of them native of Europe and Asia, the other of Africa. 



1. Conium maculatum L. Poison Hemlock. (I. F. f. 2684.) Erect, 

 much-branched, 6-15 dm. high. Lower and basal leaves petioled, the upper sessile 

 or nearly so, all pinnately dissected, the leaflets ovate in outline, thin, the ultimate 

 segments dentate, or incised; petioles dilated and sheathing at the base; umbels 



2 8 cm. broad, the rays slender, 2 4 cm. long; pedicels filiform. 4-6 mm. long in 

 fruit; flowers about 2 mm. broad; fruit 3 mm. Long, about 2 mm. wide, its ribs very 

 prominent when dry. In waste places, ( Miebec and Ont. to Del., Ind. and Mich. 

 Also in Cal. and Mex. Nat. from Europe. June -July. 



