398 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Capsules glabrous. 



Plants more or less pilose on the stems and leaves. 



Stems erect; leaves 2 cm. long or more 3. C. nutans. 



Stems prostrate; leaves usually less than lcm. long. 4. C. serrula. 

 Plants glabrous, or at least never pilose. 



Stems erect or strongly ascending; plants yellowish 



green 6. C. neomexicana. 



Stems prostrate; plants not yellowish. 



Seeds conspicuously wrinkled horizontally 17. C. glyptosperma. 



Seeds not wrinkled, pitted or smooth. 



Seeds pitted 18. C. rugulosa. 



Seeds smooth or nearly so 5. C. serpyllifolia. 



Leaf blades entire. 

 Perennials. 



Leaves strongly pubescent 7. C. lata. 



Leaves glabrous. 



Stems prostrate; involucres corolla-like 8. C. albomarginala. 



Stems erect or ascending; involucres inconspicuous. 

 Leaves scarcely if at all longer than broad, 



rounded-obtuse 9. C. fendleri. 



Leaves twice as long as broad, acute 10. C. chaetocalyx. 



Annuals. 



Stems prostrate; leaves usually very oblique at the base. 



Stipules ciliate 13. C. micromera. 



Stipules not cilitate. 



Leaves about as long as broad; stipules trian- 

 gular-subulate 11. C. serpens. 



Leaves twice as long as broad; stipules filiform. 12. C. geyeri. 

 Stems erect; leaves slightly if at all unequal at the base. 

 Capsules less than 1.5 mm. broad; plants 15 cm. 



high or less; branches divaricate 14. C. revoluta. 



Capsules more than 1.5 mm. broad; plants 30 cm. 

 high or more; branches ascending. 



Appendages of glands conspicuous, white 15. C. petaloidea. 



Appendages inconspicuous, greenish white, or 



obsolete 16. C. flagelliformis. 



1. Chamaescyce indivisa (Engelm.) Millsp. Field Mus. Bot. 2: 387. 1914. 

 Euphorbia dioica indivisa Engelm. in Torr. U. S. & Mex. Bound. Bot. 187. 1859. 

 Type locality: Near the Copper Mines, New Mexico. Type collected by Wright 



(no. 1845). 



Range: Western Texas and southern Arizona to Mexico. 



New Mexico: Hillsboro; Organ Mountains. Dry plains and low hills, in the 

 Upper Sonoran Zone. 



2. Chamaesyce stictospora (Engelm.) Small, Fl. Southeast. U. S. 714. 1903. 

 Euphorbia stictospora Engelm. in Torr. U. S. & Mex. Bound. Bot. 187. 1859. 

 Type locality: "From Kansas (Fendler, 798) to Santa Fe (Fendler, 797) and 



Dona Ana (Wright, 59), New Mexico, and Corallitas, Chihuahua." 



Range: Kansas and Colorado to Mexico. 



New Mexico: Pecos; Fort Cummings; Kingston; Sandia Mountains; Mesilla Val- 

 ley; Carrizozo; south of Roswell; Gray. Hills and plains, in the Lower and Upper 

 Sonoran zones. 



