130 UMBELLIFER^. 



* Umbels simple or imperfectly compound. 



1. HYDROCOTYLE. Linn. Marsh Pennywort. 



(From the Greek vSoyp, vxiter, and xorOXij, a cup; perhaps in allusion to the 

 form of the leaves of some species.) 



Calyx with tlie tube subcompressed and the margin of the 

 hmb obsolete. Petals ovate, entire, acute, with apex straight. 

 Fruit laterally compressed ; ribs 5, filiform, the middle and 

 lateral ones often obsolete. — Involucre few-leaved. Flowers 

 white. 



1. H. interrupta Muhl. : stem fiUform, creeping, rooting at the joints, 

 smooth; leaves peltate, orbicular, doubly crenate, 11-nerved; flowers 5 — 8 

 in axillary umbellate heads. H. vulgaris Mich. 



Wet places. Can. to Geor. Pursh. June — Aug. %. — Flowers minute, white, 

 on very short pedicels ; peduncles longer than the petioles. 



Interrupted Marsh Pennywort. 



2. H. uynbellata Linn. : stem glabrous, rooting at the joints ; leaves pel- 

 tate, orbicular, doubly crenate, 11 — 12-nerved, emarginate at the base; 

 umbels 20 — 30-flowered ; flowers distinct, pedicellate. 



Boggy places. Mass. to Flor. and Louis. June — Aug. %. — Stem creeping 

 or floating. Leaves on long petioles. Flowers minute, in umbels which are 

 sometimes proliferous. Many-flowered Marsh Pennywort. 



3. H. Americana Linn. : very smooth and shining ; leaves orbicular, 

 reniform, somewhat lobed, doubly crenate, 7 — 9-nerved ; umbels nearly 

 sessile, 3 — 5-flowered. 



Moist places. Can. to Geor. June, July. %. — Stem filiform, branchmg, 

 with long creeping suckers. Floioers greenish-white, in very small axillary 

 umbels. American Marsh Pennywort. 



4. H. ranunculoides Linn. : smooth; leaves orbicular-reniform, 5-nerved, 

 3 — 5-lobed ; umbels 5 — lO-flowered ; pedicels very short. H. cymbalarifolia 

 Muhl. 



In water. Penn. to Geor. June, July. %.. — Stem creeping or floating. 

 Leaves mostly deeply 3-lobed. Flowers white ; peduncles shorter than the pe- 

 tioles. Lobed Marsh Pennywort. 



2. CRANTZIA. iV^^^^.— Crantzia. 

 (In honor of Prof. H. J. N. Crantz, an Austrian botanist of the last century.) 



Calyx with the tube subglobose ; hmb nearly wanting. Pe- 

 tals roundish, entire, obtuse. Fruit roundish ; commissure ex- 

 cavated. Carpels unequal, with 3 marginated dorsal ribs, and 

 4 obtuse-angled grooves. — Involucre 5 — 6-leaved. 



C. lineata Nutt. : leaves cuneate-linear, obtuse, shorter than the pedun- 

 cles. Hydrocotyle lineata Mich. 



Muddy banks of streams. Mass. to Flor. July. %. — Stem smooth, creeping 

 and rooting. Leaves about 2 at each joint, 1 — 2 inches long, marked with 

 transverse Imes. Umbels 8 — 10-flowered, on long peduncles. Flowers pedicel- 

 late, white with a tinge of red. Narrowi-leaved Crantzia. 



