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II. Fruit not prickly or scaly. 
A. Fruit strongly flattened dorsally, with lateral ribs prominently winged. 
* Oil-tubes solitary in the intervals, 
6. Heracleum. Stylopodium conical: stout pubescent plants, with large and 
ternately compound leaves. 
o. EBurytzenia. Stylopodium depressed: slender caulescent branching plants, with 
pinnately dissected leaves, and white flowers. 
7. Pastinaca. Stylopodium depressed: stout caulescent plants, with yellow 
flowers, 
J. Peucedanum. Stylopodinm depressed: plants acaulescent or nearly so. 
* * Oil-tubes more than one in the intervals. 
8. Polytzenia. Caulescent and branching plants, with obsolete dorsal ribs, very 
thick corky lateral ones, and yellow flowers. 
B. Fruit not strongly flattened dorsally (usually somewhat laterally flattened). 
* Oil-tubes none. 
4, Bifora. Stylopodiumconical: seed-faceconcave : fruitof nearly distinct globose 
carpels: leaves vinnately dissected. 
28. Bowlesia. Stylopodium depressed: seed-face plane: leaves simple and lobed. 
* * Oil-tubes solitary in the intervals. 
+ Stylopodium conical. 
++ Leaflets (at least the upper) linear to filiform. 
™ Involucre wanting: flowers yellow. 
15. Foeniculum. Leaves dissected into filiform segments. 
= = Involucre present: flowers white. 
14. Ammoselinum. Low and diffuse plants, with ternately divided leaves. 
3. Trepocarpus. Leaves finely dissected: involucral bracts few and linear: fruit 
linear-oblong. 
25. Discopleura. Leaves finely dissected: involucre foliaceous: fruit ovate, the 
lateral ribs very thick and corky. 
26. Ammi. Asin the last (or the leaflets sometimes broader), but with all the 
ribs filiform. 
24. Leptocaulis. Leaves finely dissected: fruit ovate and tuberculate. 
11. Cynosciadium. Leaves with few leatlets: fruit ovoid, with thick and corky 
lateral ribs. 
++ ++ Leaflets broader. 
17. Cherophyllum. Fruit linear-oblong, with concave seed-face : calyx-teeth 
obsolete: leaves ternately decompound. 
22. Cicuta. Fruit oblong to orbicular, with plane seed-face: calyx-teeth rather 
prominent: leaves pinnately compound. 
23. Cryptotenia. Fruit linear-oblong, with plane seed-face : calyx-teeth obsolete: 
leaves 3-foliolate. 
+ + Stylopodium depressed. 
++ Flowers white. 
10. Cymopterus. Fruit with all the ribs conspicuously winged. 
20. Apium. Fruit very small, with equal, broad and corky ribs. 
16. Apiastrum. [Truit with obscure or obsolete ribs. 
++ ++ Flowers yellow. 
21. Zizia. Tall and branching plants, with broad leaflets, and fruit with filiform 
ribs. 
