102 BOTANICAL GAZETTE, [ May, 
Notes on Umbellifere of’ E, United States, IV. 
a 
JOHN M. COULTER AND J. N. ROSE, 
(WITH PLATE Iv.) 
HYDROCOTYLE Tourn.—Fruit (and carpels) strongly 
flattened laterally, more or less orbicular : carpel with 5 pri- — 
single species) ; dorsal ribs marginal, broad or filiform; in- 
creeping stems, orbicular-peltate or reniform leaves, af 
F 
Small white flowers in simple or proliferous umbels. Flow-_ 
ering all summer. In figure 44, a indicates the oil-bearing 
layer, 6 ordinary parenchyma, ¢ the layer of strengthening 
cells. 
* Fruit with pericarp thin except at the broad thick corky dorsal 
and lateral ribs (figures 43-50): leaves orbicular-peltate, crenate: pedun- 
cles as long as petioles, all from slender creeping rootstocks 
+ Fruit notched? at base and apex; intermediate ribs corky (figures 
43-48). iy 
_ 1. He ambellata L, Spec. 234. Umbels many-flowered, 
simple (sometimes proliferous): pedicels 2 to 6 lines long: 
fruit about 14 lines broad, strongly notched (figs. 43; 44)- 
—Massachusetts to Minnesota and southward to the Gulf. 
7 7 weners Kelloge, Pre. Calif; Acad. 31197 (ue 
bels mostly proliferous, with 5 to 20-flowered whorls: pedi- 
cels 1 to 3 lines long: fruit about a line broad, but slightly — 
notched (figs. 45, 46).—Texas, to Arizona and California. 
This species is too near H. umbellata. In the great majority 
of specimens they can be distinguished easily, but the occa- 
sional forms of H. prolifera which are not proliferous, ang 
1This characte 
studied. In the European H, Vulgaris the 
mis in places covering the fruit with oil vesie 
*This notching may not be apparent except in fully matured fruit. 
r of @ prominent oil-bearing layer differs from any other soe 
oil-bearing layer breaks through the epi 
les. é 
Bie ee. SP see 
