calyx teeth obsolete, the stylopodium conic; carpophore divided to the base; fruit 

 3.5-4 mm. long, 1.5-2 mm. broad, oblong, slightly compressed laterally, glabrous, 

 the prominent ribs acute or obtuse; oil tubes solitary in the intervals and 2 on the 

 commissure, the seed face plane or slightly concave. 



Introd. in marshes and low areas in coastal and s. Tex., Mar.-May; a Medit. 

 species that is adv. throughout the W. Hemis. 



12. Zizia Koch 



A genus of about 4 species, primarily of eastern United States and adjacent 

 Canada, but extending to the Pacific Northwest. 



1. Zizia aurea (L.) Koch. Golden Alexanders. 



Erect caulescent usually branching perennial from fascicled roots, 4-8 dm. high; 

 basal leaves petiolate, ovate to orbicular, to 1 dm. long and 12 cm. wide, biternate 

 or the middle leaflet pinnatifid; leaflets ovate to lanceolate, distinct, sharply serrate; 

 cauline leaves like the basal, becoming narrowly lanceolate and confluent upwards; 

 inflorescences of compound umbels; peduncles 5-15 cm. long; involucre lacking; 

 involucel of a few inconspicuous linear acute bractlets 1-3 mm. long, shorter than 

 or equaling the pedicels; rays 10 to 15, spreading-ascending, unequal, 1-3.5 cm. 

 long; pedicels 2-3 mm. long; the central flower of each umbellet sessile or sub- 

 sessile; flowers yellow; calyx teeth prominent; stylopodium lacking; fruit oblong- 

 ovoid, 2-4 mm. long, 1.5-2 mm. broad, compressed laterally, the ribs filiform; oil 

 tubes solitary in the intervals and 2 on the commissure; seed face slightly concave. 



In wet sandy woodlands and sandy-clay floodplains in Okla. (Waterfall) and 

 the e. third of Tex., Apr.-Aug.; from e. Can., s. to Fla., w. to Sask., Mont, and 

 Tex. 



Zizia aptera (Gray) Fern., with leaflets of stem leaves not more than 3, occurs 

 in Oklahoma, but it is usually in less moist areas than the habitat of Z. aurea. 



13. Apium L. Celery 



Plants slender or stout, erect, ascending or prostrate, caulescent (usually), 

 branching, herbaceous, glabrous, annual, biennial or a somewhat woody-based 

 perennial from taproots or creeping rootstocks rooting at the nodes; leaves simply 

 pinnate to ternate-pinnately decompound; inflorescence of compound (rarely sim- 

 ple) umbels, the peduncles lateral and terminal or some umbels sessile; involucre 

 and involucel lacking to conspicuous; rays usually few, spreading-ascending, the 

 pedicels spreading to ascending; flowers white or greenish, the calyx teeth minute 

 or obsolete, the stylopodium short-conic to depressed; carpophore entire, shortly 

 bifid or more or less deeply 2-cleft; fruit oblong-oval to orbicular or ellipsoid, com- 

 pressed laterally and somewhat constricted at the commissure, glabrous or rarely 

 somewhat setulose, the prominent filiform ribs subequal and obtuse; oil tubes soli- 

 tary in the intervals and 2 on the commissure, the seed face plane. 



A cosmopolitan genus of about 30 species. 



1. Plant annual; leaves pinnately or ternate-pinnately decompound, the leaflets 

 filiform to linear 1. A. leptophyllum. 



1. Plant perennial or biennial; leaves pinnate, the leaflets orbicular to ovate 



2. A. graveolens. 



1. Apium leptophyllum (Pers.) F. v. Muell. Fig. 582. 



Plant annual, alternately branched above, 5-60 cm. high; leaves oblong-ovate, to 

 10 cm. long and 8 cm. wide, 3- or 4-pinnately decompound, the leaflets linear to 

 filiform; umbels simple or compound, sessile or pedunculate, the peduncles to 2 

 cm. long; involucre and involucel lacking; rays 3 to 5, 1-2.2 cm. long; pedicels 

 2-8 mm. long; calyx teeth inconspicuous; carpophore shortly 2-cleft; fruit ovoid, 

 1.2-3 mm. long, 1.5-2 mm. broad, glabrous. Apium ammi (Jacq.) Urban. 



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