EUPHORniACE.E. (SI'LKGE FAMILY.) 82o 



Filaments united into a central column. Soods subglobose, ronghened or 

 reticulated, not carunculate. — Erect herbs or underslind.s. with purpli»h 

 iuicc : leaves alternate, u&ually stipulate, entire (in ours). 



1. A. humiliS, Miill. Stem about one foot ]iit,'li, much Jjnuuhed, silky 

 or strigose-pubcscent, branches si)rea(lini; : leaves narrowed ut the b:u*<?. hpatu- 

 late or obovate-lanceolate or linear-lanceolate, acute, hp;irin;,'lv puhcHt-fut ; 

 raceme much shorter than the leaves, on very short peduncles. — S, Colonidu 

 and southward. 



3. CROTON, L. 



Stamiuate calyx 4 to 6-parted. Petals often present, Init small or nidi- 

 mentary, alternating with the glands of a central disk. Stunu-nx 5 lo 

 many, on a hairy receptacle. Pistillate calyx usually 5-ji;irtod, but the |K'talit 

 mostly obsolete. Seeds smooth and shining, carunculate. — Herbs or »ljruhn, 

 scurfy or stellately hairy or sometimes glandular : leaves alternate, entire or 

 repand. 



1. C. Texensis, INIiill. Covered with a close canescent stellate pul)«t- 

 cence, dichotomously branched or spreading, 1 to 2 feet higli : leaves lance- 

 ovate, oblong, or linear-lanceolate: dioecious; racemes of stamiuate flowen* 

 short : ovary stellate-tomentose ; styles twice or thrice dichotomously 2-parted. 

 — S. Colorado and southward. 



4. EUPHORBIA, L. 



Flowers monoecious, included in 4 to 5-lobed involucres, the lobes usually 

 alternating with as many fleshy glands which are rounded or often jtetaloid- 

 margined or crescent-shaped. — Mostly herbs : leaves opposite or alternate t>r 

 the upper ones verticillate : involucres terminal or in the forks, the sterile 

 flowers lining the base and each from the a.xil of a little bnu-t, the fertile 

 flower solitary in the middle of the involucre, soon protruded on a lonj; 

 pedicel. 

 A. GlaTids of the involucre loith petal-like, imuaUy v:hUc or rose-col or cd, tn<.<<. <■, 



toothed margins or appcndotjcs. 

 § 1. Leaves all similar, ojjposite, on short petioles, sumll, oblique at lHisr,/uniishrtl 

 with oivl-shaped or scaly and often frinfjcd stipulm : stems much branched, 

 spreading or usually 2)rocumhcnt : involucres solitary in the forks of the branches 

 or in terminal or lateral clusters, small, uu'fh 4 glands. 



* Seeds smooth and even : leaves entire, glabrous. 



1. E. petaloidea, Engelm. Glabrous : stems protnimlH-nt or ;im . n.uui; : 

 leaves attenuate to the scarcely oblique ba-so, oblong-linear or linmr, rvtu.'io or 

 emarginate : involucres solitary, campanulatc, lobes haiiy In'iu'ath the glamlii 

 within, the broadly campanulatc ai)pondages conspicuous ; jH-dunclcs longt-r 

 than petioles: seeds reddish, with rounded angles. — From Cdttrado to Ne- 

 braska and eastward to the Mississippi. 



2. E. flagelliformis, Kngilm. Distinguished from th.- bust by tho 

 smaller involucre bearing very snuvU and almost naked glands, often less than 



