SPURGE FAMILY 23 



4. Polygala subspinosa S. Wats. Spiny Milkwort or Polygala. Fig. 3014. 



Polygala subspinosa S. Wats. Amer. Nat. 7:299. 1873. 

 Polygala lasseniana Heller, Leaflets West. Bot. 2:230. 1940. 



Low, much-branched shrub, 5-15 cm. high, the stems several to many from a stout woody 

 caudex, pallid green, finely pubescent with spreading hairs or glabrate, the branches spiny-tipped. 

 Leaves 1-2 cm. long, narrowly obovate to elliptic, narrow at the base, glabrous or sparsely 

 puberulent, coriaceous ; racemes 1-4-fiowered, the axis indurate and spiny-tipped ; bracts narrowly 

 lanceolate, membranous and colored ; pedicels 3-9 mm. long ; sepals 4-6 mm. long ; corolla rose- 

 purple and yellow, glabrous ; wing-petals obliquely ovate, 10 mm. long ; keel with blunt porrect 

 entire beak; capsule 6-7 mm. long, 4-5 wide, reticulate, sparsely hispidulous on the margin. 



Dry desert hillsides, Upper Sonoran Zone; Lassen County, California, western Nevada to western Colorado, 

 northern Arizona and northern New Mexico. Type locality : Silver City, Nevada. May-June. 



Polygala subspinosa var. heterorhyncha Barneby, Leaflets W^est. Bot. 3: 194. 1943. Habit much the 

 same as the typical species; beak of the keel emarginate on the lower side at about the middle with a deep 

 rounded notch. Chloride Clifif, Death Valley, California, and in the Spotted Range, Nye County, Nevada, the 

 type locality. 



5. Polygala acanthoclada A. Gray. Desert Milkwort or Polygala. Fig. 3015. 



Polygala acanthoclada A. Gray, Proc. Amer. Acad. 11: 73. 1876. 



Low shrub, 1 m. high or less, intricately divergent-branched, branches densely pilose, canes- 

 cent, the branchlets indurate and ending in a sharp spiny tip. Leaves spatulate to linear-spatulate, 

 6-15 mm. long, puberulent with incurved spreading hairs; racemes 2-3-flowered; flowers yellow- 

 ish; wings obovate or oval, rounded at base, 4-5 mm. long, glabrous; keel not beaked; capsule 

 oval, 4.5-5 mm. broad ; aril apical, 1 mm. long. 



Desert ranges, Upper Sonoran Zone; Providence Mountains, California, and western Nevada to southern 

 Colorado and northwestern Arizona. Type locality: San Juan Valley, Colorado. June-July. 



Family 79. EUPHORBIACEAE.* 

 Spurge Family. 



Monoecious or dioecious trees, shrubs or herbs with milky or acrid juice. Leaves 

 simple, alternate or opposite, entire, toothed or lobed. Stipules present or absent. 

 Flowers usually apetalous, often without a calyx. Stamens few to many, anthers 

 2-celled, filaments free or united. Ovary 3-4-celled, more rarely 1- to many-celled. 

 Ovules 1-2 in each cell; styles equaling the number of cells, simple or variously 

 divided. Fruit various, in ours usually a 3-lobed capsule separating into 2-valved 

 carpels from a persistent axis. Seeds fleshy or oily. 



About 250 genera and 4,500 species of wide geographical distribution, mainly in tropical and subtropical 

 regions. 



Flowers not subtended by an involucre simulating a calyx; perianth present in the staminate flowers, present 

 or absent in the pistillate flowers. 

 Ovules 2 in each cell; shrubs. 1. Tetracoccus. 



Ovules 1 in each cell; herbs or shrubs. 



Leaves entire, crenate or dentate, not palmately lobed; capsules glabrous or pubescent. 



Stamens united in a column; petals present (in ours) in both staminate and pistillate flowers. 



3. D it axis. 

 Stamens free; petals absent in both staminate and pistillate flowers. 



Herbage of stellate or scale-like hairs. 



Ovary 1-celled; plants annual; pistillate flowers without calyx. 2. Eremocarpus. 



Ovary 3-celled; plants perennial herbs or shrubs; pistillate flowers with calyx. 



Seeds carunculate; leaves entire; herbs (sometimes woody at base). 



4. Croton. 



Seeds ecarunculate; leaves crenate; shrubs. 5. Beniardia. 

 Herbage glabrous or of simple hairs. 

 Herbage of simple hairs. 



Stigma-lobes finely dissected; plant without stinging hairs. 6. Acalypha. 



Stigma-lobes simple; plants with stinging hairs. 7. Tragia. 



Herbage glabrous. 8. Stillingia. 



Leaves palmately lobed; capsule usually spiny. 9. Ricinus. 



Pistillate and staminate flowers surrounded by one involucre simulating a calyx; perianth none or present as a 



single scale. 10. Euphorbia. 



1. TETRACOCCUS Engelm. ex Parry, W. Amer. Sci. 1: 13. 1885. 



Dioecious shrubs with opposite or alternate, sometimes fascicled, leaves. Staminate 

 flowers in clusters, apetalous; sepals 4-10; stamens 4-9, surrounding- the lobed disk. 

 Pistillate inflorescence solitary; flowers apetalous, with disk; calyx 6-10-parted. Ovary 

 3-4-celled, the cells 2-ovuled; styles 3-4, entire, linear or dilated at apex. Capsule lobed. 



*Text, except the genus Euphorbia, contributed by Roxana Stinchfield Ferris. 



