COULTER AND ROSE—NORTH AMERICAN UMBELLIFERAE. 23 
FRUIT NOT STRONGLY FLATTENED DORSALLY, usually more or less laterally 
flattened, 
Oil tubes solitary in the intervals. 
Stylopodium conical, 
Leaflets (at least the upper) linear to filiform. 
Involucre wanting; introduced. 
Flowers white..........-.-.-.------.----------- Coriandrum, 252. 
Flowers yellow .....--..-.--------------- ~as---- Foeniculum, 254. 
Involuere present; flowers w hite (except Cuminum). 
Low and diffuse, with ternately divided leaves. . 
Ammoselinum, 88. 
Taller and erect. 
Leaves finely dissected. 
Fruit ovate. 
Fruit smooth.........2....2...-....----- Ptilimnium, 117. 
Fruit bristly or tuberculate.........-.---- Spermolepis, 87. 
Fruit linear-oblong. 
Fruit smooth; flowers white -......------ Trepocarpus, 85. 
Fruit bristly; flowers rose color......-...-.--- Cuminum, 253. 
Leaves with few leaflets. 
Lateral ribs thick and corky; southern...Cynosciadium, 120. 
Ribs all filiform; western........2........2...-. Carum, 103. 
Leaflets broader. 
Seed face concave ...........----------------- Chaerophyllum, 58. 
Seed face plane. 
Fruit oblong to orbicular. 
Involucre of few bracts or none ..........2-.------- Cicuta, 93. 
Involucre conspicuous ........-..-------- Taeniopleurum, 102. 
Fruit linear-oblong ............. .-..-------------- Deringa, 101. 
Stylopodium flat or wanting. 
Flowers white. 
Ribs thick and corky, at least the laterals. 
Dorsal ribs filiform; aquatic. 
Leaves reduced to hollow petioles ......2...... Lilaeopsis, 123. 
Leaves pinnate or decompound...........-.---- Oenanthe, 121. 
All the ribs prominent and corky. 
Ribs wing-like and much wrinkled when young. 
Rhysopterus, 185. 
Ribs broad and not wrinkled. 
Fruit small (not more than 2 mm. long), flattened laterally. 
Involucre wanting ....-..--.------------------ Apium, 86. 
Involucre present. ....-.---------------------+-- Amim, 255. 
Fruit larger, ovoid-globose.........2........---- Aethusa, 254, 
Ribs filiform or obsolete. 
Ribs filiform.........0.22-22.--2--.--2------------ Leibergia, 108. 
Ribs obscure or obsolete. -..--------------------- Apiastrum, 71. 
Flowers yellow. 
Ribs equal, broad, and corky. 
Low and cespitose; high alpine.........-...-2------- Oreoxis, 143. 
A foot or more high; in the foothills or low ground. 
Fruits tuberculate-roughened; calyx teeth evident. 
Harbouria, 92. 
Fruit smooth; calyx teeth obsolete ........---- Petroselinum, 253. 
Ribs winged or filiform. 
