tSi LXVII. UMBELLIFER^. Hydrocotyle. 



Conspectus of the Genera. 

 * Plants native or naturalized. 



i Seeds flattish inside. Simn. 8 



fFr. laterally compressed. {Seeds grooved inside. CwiiMOT. 28 



\ Petals radiant. . Heracletim. 23 



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

 I \ with smooth ribs. . Ligusticiim. 17 



("of entire bracts. iFr. scarcely compressed, ? with bristly ribs. . Osmorhiza. 27 



'^ \ Rays 2—4. . . Sanicula. 3 



S ' ^ Fr. very bristly. ( Rays many. . . Daucus. 25 



o $ several. \ Fruit not bristly DiscopleuTum. 5 



§■ f Involucre lofcleflbracts, (one only, bipinnatifid Erisenia. 29 



§ < Cal. limb ^ Leaves 3-parted, . . Ci yptoteenia. 9 



o / obsolete. \ Leaves finely divided. . ClicErophyllwm.X 



S js < ("Fr. laterally compressed. ( Calyx limb 5-toothed. . . Cicuta. 7 



.c C ^ j 1 Uhe margin singly winged. . . Arcfiemora. 21 



^ g 1 Fr. dorsally compressed, J the margin doubly winged. , . Ardmngeiica. 20 



C I p Llnvoluc. 0. L Fruit scarcely compressed, ovoid globose JEthusa. 16 



" I ^ Lvs. linear. . Crantzia. 2 



S < with 4— 30 pedicellate or subsessile flowers. { Lvs. roundish. Hydrocotyle. I 



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



( Carpels with 5 winged ribs Thaspium. 15 



< Carpels with S filiform ribs. . . . . Zizia. 10 

 f Involucels minute. ( Carpels smooth, ribs obsolete. . . . Potytcenia. 24 

 < In volucels very large. Leaves simple, perfoliate Bupleunmi. 6 



Flowers yellow. (luvolucels 0. Fruit much compressed dorsally Pastinaca. 22 



* * Cultivated exotics, not naturalized. 



( Fruit laterally ^ roundish. . Apium. 13 



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



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



< of I entire bract. ( Petals radiant Coriandrum. 30 



i white. ( Involucre of a few clefl bracts Petroselinum. 14 



■ Flowers ( yellow Fasniculum. 19 



Suborder 1.— O RTHOSPERMJ3. 



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

 1. HYDROCOT'f'LE. 



Gt. iSop, water, kotvXt], a vessel ; the concave leaf often holds water. 



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

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

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

 ceous, creeping, usually aquatic idants. Umbels simple. Involucre few- 

 leaved. 



1. H. Americana. Pennyv:orf. 



Smooth and shining; st. fiiJiform, procumbent; lvs. reniform-orbicular, 

 slightly lobed, crenate ; umbels sessile, 3— 5-flov/ered ; 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, 1 — 2' 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. Mlchx.) 



Smooth ; lvs. peltate, orbicular, crenate ; mnbcls capitate, proliferous, sub- 

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

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

 peltate, thin, 8—10" diam. Petioles 2—3' long. Peduncles longer than the 

 petioles. Flowers subsessile, in clo.se 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 ; lvs. peltate, orbicular, crenate, emarginate at base, on long peti- 

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

 pedicellate. — ^l- In ponds and bogs, Mass. ! to La., rare. Stems creeping, often 

 submersed, several inches long. Leaves 8 — 12" 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. 



