-284: LXVII. UMBELLIFER^E. , HYDROCOTTLE. 



Conspectus of the Genera. 

 * Plants native or naturalized. 



$ Seeds flattish inside. Slum. 8 



f Fr. laterally compressed. \ Seeds grooved inside. Conium. 28 



$ Petals radiant. . Heracleum. 23 



i Fr. dorsally compressed. (. Petals all equal. . Conioselinum. 18 



( with smooth ribs. . Ligusticum. 17 



{ of entire bracts. LFr. scarcely compressed, \ with bristly ribs. . Osmorhiza. 27 



\ Kays 24. . . Sanicula. 3 



( Fr. very bristly. ( Rays many. . . Daucus. 25 



< several. Fruit not bristly Discopleurum. 5 



of cleft bracts, (one only, bipinnafifid F.rigenia. 29 



( Cal. limb ^ Leaves 3-parted, . . Ciyptotcenia. 9 



o / obsolete, it Leaves finely divided. . Cfi.cerophytlum.26 



JS < (Fr. laterally compressed. ( Calyx limb 5-toothed. . . Cicuta. 



\S ^ the margin singly winged. . . Archemora. 21 



g l Fr. dorsally compressed, c the margin doubly winged. . . Arcfatngelica. 20 



p Unvoluc. 0. L Fruit scarcely compressed, ovoid-globose JEthusa. 16 



$ Lvs. linear. . Crantzia. 2 



< with 430 pedicellate or subsessile flowers. < Lvs. roundish. Hydrocotyle. 1 



Umbels simple, ( densely capitate, with 50 or more sessile flowers. . . Eryngium. 4 



( Carpels with 5 winged ri 

 \ Carpels with 5 filiform ribs. 

 Involucels minute. ( Carpels smooth, ribs obsolete. 



Thaspium. 15 



Zizia. 10 



Polyt&nia. 24 



Bupleurum. 6 



Pastinaca. 22 



Involucels very large. Leaves simple, perfoliat 

 Flowers yellow. ( Involucels 0. Fruit much compressed dorsally. 



* * Cultivated exotics, not naturalized. 



( Fruit laterally ^ roundish. . Apium. 13 



(Petals all equal. < compressed, if oval. . . Carum. 11 



( Involucre 0, or < (Fruit not compressed. . . Pimpinella. 12 



< of 1 entire bract. ( Petals radiant Conundrum. 30 



$ white. ( Involucre of a few cleft bracts Petroselinum. 14 



Flowers ( yellow Fceniculum. 19 



SUBORDER 1. O RTHOSPERMJE. 



The inner surface of the seeds and albumen flat or nearly so. 

 1. HYDROCOTtLE. 



Gr. vSup, water, KOTV\TI, a vessel; the concave leaf often holds water. 



Calyx obsolete ; petals equal, ovate, spreading, entire, the point 

 not inflected ; styles shorter than stamens ; fruit laterally flattened, 

 the commissure narrow; carpels 3-ribbed, without vittae. Herba- 

 ceous^ creeping ', usually aquatic plants. Umbels simple. Involucre few- 

 leaved. 



1. H. AMERICANA. Pennywort. 



Smooth and shining; st. fiJiform, procumbent; Ivs. reniform-orbicular, 

 slightly lobed, crenate ; umbels sessile, 3 5-flowered ; fr. orbicular. % A small, 

 delicate plant, growing close to the moist earth beneath the shade of other vege- 

 tables, Can. to S. Car. Stems branching, 2 6' long. Leaves thin, 12' diam., 

 on petioles 2 3' long. Flowers greenish -white, small, nearly sessile, in sim- 

 ple, capitate, sessile, axillary umbels. Jn. Aug. 



2. H. INTERRUPTA. Muhl. (H. vulgaris. Michx.} 



Smooth; Ivs. peltate, orbicular, crenate; umbels capitate, proliferous, sub- 

 sessile, about 5-flowered ; fr. acute at base. Tj. In wet places, New Bedford, 

 Mass. T. A. Greene, rare. Root and stem creeping. Leaves almost centrally 

 peltate, thin, 810" diam. Petioles 23' long. Peduncles longer than the 

 petioles. Flowers subsessile, in close umbels which become whorls in inter- 

 rupted spikes by other umbels being successively produced on the extending 

 peduncle. Jn. 



3. H. UMBELLATA. Umbellate Pennywort. 



Smooth ; Ivs. peltate, orbicular, crenate, emarginate at base, on long peti- 

 oles ; scapes about as long as the petioles ; umbels simple, often proliferous ;fts. 

 pedicellate. 1\. In ponds and bogs, Mass. ! to La., rare. Stems creeping, often 

 submersed, several inches long. Leaves 812" diam., notched at base so as to 

 appear reniform. Petioles a little eccentric, and with the scapes slender, float- 

 ing or erect, and 4 6' long. Umbels 20 30-flowered, the . upper pedicel often 

 prolonged and umbellate. May Jl. 



