AMMIACEAE 
** Involucre conspicuous: fruit with secondary ribs and reticulations. 
Seed-face concave. 
Stylopodium conic. 
Fruit bristly, elongated. 
Fruit smooth, of almost distinct globular carpels. 
Stylopodium obsolete or flat. 
Seed-face essentially flat. 
B. Fruit with distinct oil tubes. 
Inflorescence glomerate, the flowers aggregated into dense heads. 
Inflorescence manifestly umbellate. 
Fruit strongly flattened dorsally, the lateral ribs of the carpels more or less 
prominentiy winged. 
Oi 
tubes solitary in the intervals. 
Stylopodium conic. 
Fruit not notched at the apex, the carpels not very flat. 
Fruit notched at the apex, the carpels very flat. 
Stylopodium obsolete or flat. 
Plants caulescent. 
Corolla white. 
Fruit armed with barbed spines. 
Fruit spineless. 
Leaf-blades pinnately dissected: fruit with filiform dorsal 
Leaf-blades ternately or pinnately compound: fruit with 
Fruit with prominent dorsal ribs, the lateral ribs not corky thick- 
ribs. 
b. Fruit not strongly flattened, sometimes turgid. 
stout dorsal ribs. 
Corolla yellow. 
Plants acaulescent or essentially so. 
Oil tubes more than one in the intervals. 
Plants caulescent. 
Fruit with obsolete dorsal ribs, the lateral ribs corky thickened : 
corolla yellow. 
ened : corolla white. 
Leaf-blades 1-2-ternately divided. 
Leaf-blades much more divided. 
Plants acaulescent or essentially so. 
Lateral wings of the fruit thin. 
Lateral wings of the fruit thick. 
Fruit more or less flattened laterally, or sometimes slightly dorsally flattened. 
Oil tubes solitary in the intervals. 
Stylopodium conic. 
bd leaves with narrowly linear segments. 
nvoluere wanting: naturalized species. 
Corolla white. 
Corolla yellow. 
Involucre present. 
Low plants with diffusely branched stems, 
Taller plants with erect. not diffusely branched, stems. 
Leaves with finely dissected blades, the segments numerous. 
Fruit with thick corky ribs, at least the lateral ones. 
Fruit about as thick as long. 
Fruit smooth. 
Fruit bristly or tuberculate. 
Fruit long and narrow. 
Leaves with few segments. 
Upper leaves with relatively broad segments. 
Seed-face concave. 
Fruit glabrous or merely pubescent. 
Fruit spiny. 
Seed-face flat. 
Fruit nearly as broad as long. 
Fruit linear-oblong. 
Stylopodium obsolete or flat. 
Corolla white. 
Dorsal ribs filiform : plants aquatic. 
Dorsal and lateral ribs corky and prominent. 
Stylo ium flat or flattish. 
eter regular or nearly so, the petals with inflexed 
tips: rays of the secondary umbels not concreted 
Pase. 
at the base. 
Corolla markedly irre 
rays of the secondary umbels concreted at the 
lar, the 
Stylopodium obsolete. 
Fruit with obsolete or obscure ribs. 
Corolla yellow. 
Fruit with winged ribs. | 
Fruit with merely filiform ribs. 
Oil tubes more than one in the intervals. 
Stylopodium conic. i ^ 
Fruit rounded, the globular earpels with slender inconspicuous 
ribs. 
Fruit of an ovate or oblong type. 
Mature carpels with stout equal ribs. 
Mature carpels with filiform ribs. 
Stylopodium flat or obsolete, 
Seed-face grooved or markedly concave: plants acaulescent or essentially so. 
tals cleft at thea 
2. 
857 
CENTELLA. 
. WASHINGTONIA. 
. BIFORA. 
. BUPLEURUM. 
. BOWLESIA. 
. ERYNGIUM. 
. Ox YPoLIS. 
. HERACLEUM. 
. DAUCUS. 
. EURYTAENIA. 
. ANGELICA, 
. PASTINACA. 
. LOMATIUM. 
38. POLYTAENIA. 
35. ANGELICA. 
34. CONIOSELINUM. 
. LOMATIUM. 
97. CYMOPTERUS. 
26. 
32. 
24. 
. CORIANDRUM. 
. FOENICULUM. 
. AMMOSELINUM. 
. PTILIMNIUM. 
. SPERMOLEPIS. 
. TREPOCARPUS. 
. CYNOSCIADIUM, 
. CHAEROPHYLLUM. 
. TORILIS. 
. CICUTA. 
. DERINGA. 
. LILAEOPSIS. 
. APIUM. 
. AMMI. 
SIUM. 
. APIASTRUM. 
. THASPIUM. 
. ZIZIA. 
BERULA. 
LIGUSTICUM. 
EULOPHUS. 
