IM 
thin cordate to reniform, half to over an inch broad, 8 to 5-lobed 
(lobes entire or toothed), on long slender petioles: umbels 1 to 4- 
flowered, on short peduncles: fruit about a line long, sessile or 
nearly so. 160.) — IJ. tenera Sprcng. B. geraniifolia 
Cham. & Schlecht. B. iiodijiora Presl. 
Damp shady places, from the Sacramento Valley, California, and south- 
ward, extending into Arizona (Pringle) and Texas (Hall, Wriglt^, Minx 
Croft). FI. April and May. 
58. HYDROCOTYLE Linn. Gen. n. 825.-*Lovv herba- 
ceous perennials, growing in or near water, with slender creeping 
stems, orbicular-peltate or reniform leaves, and small white flow- 
ers in simple or proliferous umbels. 
The strong lateral flattening of the carpels and the prominent hypo- 
dermal oil-bearing layer of this genus are strikingly different from those 
of any other of our genera. In the European H. vulgaris the oil-bearing 
layer breaks through the epidermis in places, covering the fruit with oil- 
vesicles. 
* Fruit with pericarp thin except at the broad thick corky 
dorsal and lateral ribs : involucre of short ovate bracts : leaves 
orbicular -peltate., crcnate : peduncles as long as 'petioles., both frotn 
slender creeping rootstocks. 
•j* Fruit notched'^ at base and apex ^ intermediate ribs corky. 
1. H. umbellata L. Spec. 284. Descending branches of 
the rootstock with round tubers: umbels many-flowered, simple 
(sometimes proliferous); pedicels 2 to 6 lines long: fruit strongly 
notched, 1 line long, about lines broad, with dorsal ribs prom- 
inent but obtuse. (Fig. 161.) 
From Massachusetts to Florida, westward to Minnesota and Texas, and 
extending into Mexico. 
Forms collected on ballast near Philadelphia y^Mart indale). Port Eads, 
Louisiana {Langlois), and Vancouver Island (Macoun), are unusually pro- 
liferous, sometimes so much so as to give 'the impression of compound 
umbels. 
2. H. prolifera Kellogg, Proc. Calif. Acad. i. 15. Tuber- 
ous as in the last: umbels mostly proliferous, with 5 to 20-flowered 
whorls; pedicels 1 to 8 lines long: fruit but slightly notched, a line 
long or slightly broader, with dorsal ribs prominent and more 
7 This notching* niity not be apparent except in full}' matured fruit. 
