386 
5, Jatropha. Calyx corolla-like, the staminate salverform: armed with stinging 
hairs, 
++ + Flowers in terminal spikes or spike-like racemes: stamens inflexed in bud. 
6. Croton. Petals usually present in pistillate flowers. 
++ ++ + lowers in loose terminal racemes: stamens 10; anthers with united backs. 
7. Manihot. Apetalous: calyx petal-like. 
++ ++ ++ ++ Flowers in axillary spikes or racemes (except No. 11), apetalous (except 
No. 8): stamens usually 8 or more: anthers erect in bud. 
8. Argythamnia. Petals and sepals 5: stamens 10 to 15, united: styles bifid, 
linear. 
9. Bernardia. Sepals 3 (or 4): stamens 3 to 20: stigmas sessile, very short, 
2-lobed: pistillate flowers terminal, sessile. 
10. Acalypha. Calyx 3 to 5 (usually 4)-parted: stamens mostly 8: fertile (lowers 
in the axils of leafy bracts: stigmas finely dissected. 
11. Ricinus. Racemes terminal, subpaniculate: calyx 3 to 5-parted: stamens 
very numerous; filaments repeatedly branched: styles 2-parted. 
+e te t+ t+ ++ Flowers fasciculate (the pistillate solitary) in axillary clusters. 
12. Ricinella. Calyx 5-parted: styles 3-parted: leaves in alternate fascicles. 
+++ te 44 4+ ++ Flowers apetalous, in racemes or spikes: stamens 2 or 3: styles sim- 
ple. 
13. Tragia. Flowers in lateral or terminal racemes, pistillate below: hirsute or 
pubescent, : 
14. Stillingia. Flowers in terminal spikes, pistillate below: glabrous. 
1. BUPHORBIA L. (SrurGe.) 
Herbs or shrubby, with milky acrid juice, moneecious flowers 
included in a cup-shaped 4 or 5-lobed terminal involucre resembling a 
calyx or corolla, numerous sterile flowers lining the base of the invo- 
lucre, single stamen with separate globular anther-cells, the solitary 
fertile flower soon protruding on a long pedicel from the middle of the 
involucre, three 2-cleft styles, and a pod separating into three 1-seeded 
‘arpels which split elastically in two valves. 
A. Glands of the invelucre with petal-like, usually white or rose-colored, margins or 
appendages, 
$1. Leaves opposite (rarely verticillate), more or less oblique at base, subsessile or short- 
petioled; stipules lanceolate to filiform, persistent (except in No. 3): involucres sol- 
itary in the forks or in terminal or pseudo-lateral clusters, small, with 4 glands,— 
ANISOPHYLLUM. 
* Rigid hirsute (or strigose) perennials, with subsessile entire leaves attenuate at apex, 
solitary involucres, and the 4 glands furnished with lobed appendages. 
+ Seeds smooth, 
€ 
1, E. acuta Engelm. Stems numerous, 1 to 3 dm. high, leafy: leaves ovate-lan- 
ceolate, acute, mucronate, 1 to2 cm. long; stipules filiform: involucre campanulate, 
axillary, the triangular lobes ciliate: pod white villous: seed subeubical, 2 min. 
long.—Stony prairies of western Texas and along the Pecos, 
+ + Seeds wrinkled or rugose. 
2. E.lataEngelm. Canescent with appressed pubescence: stems (10 to 30 cm. high) 
from a woody rootstock, spreading: lower internodes longer than the leaves, upper- 
most very short: leaves triangular-ovate and abruptly attenuate or oblong and rather 
