WOOTON AND STANDLEY FLORA OF NEW MEXICO. 509 



1. Acerates viridiflora (Raf.) Eaton, Man. Bot. ed. 5. 90. 1829. 

 Asdepias viridiflora Raf. Med. Repos. N. Y. 5: 360. 1808. 



Type locality: "In several parts of Maryland and Pennsylvania, mostly in fields." 

 Range: Saskatchewan and New England to Florida and Mexico. 

 New Mexico: Sierra Grande (Standley 6060). Plains and dry hills, in the Upper 

 Sonora Zone. 



2. Acerates ivesii (Britton) Woot. & Standi. 



Asdepias lanceolata Ives, Amer. Journ. Sci. 1: 252. 1819, not Walt. 1788. 

 Acerates viridiflora ivesii Britton, Mem. Torrey Club 5: 265. 1894. 

 Type locality: "On the sandy plains east of Cedar Hill, in New Haven." 

 Range: Nebraska and South Dakota to Arizona and New Mexico. 

 New Mexico: Santa Fe Canyon; Kingman. Plains and low hills, in the Upper 

 Sonoran Zone. 



3. Acerates rusbyi Vail, Bull. Torrey Club 25: 37. 1898. 

 Type locality: Oak Creek, Arizona. 



Range: New Mexico and Arizona. 



New Mexico: Near Tesuque; south of Roswell. Upper Sonoran Zone. 



4. Acerates auriculata Engelm. in Torr. U. S. & Mex. Bound. Bot. 160. 1859. 

 Asdepias auriculata Holzinger, Bot. Gaz. 17: 125. 1892. 



Type locality: Dry ravines near the Copper Mines and along the Mimbres, New 

 Mexico. Type collected by Bigelow. 



Range : Nebraska and Kansas to New Mexico and Texas. 



New Mexico: Lower Plaza; Organ Mountains; White Mountains. Dry hills, in 

 the Upper Sonoran and Transition zones, 



5. ASCLEPIAS L. Milkweed. 



Perennial herbs of various habit, with opposite, alternate, or verticillate leaves, 

 the flowers in pedunculate umbels, borne mostly near the top of the stem, pseudo- 

 terminal; calyx small, green, often with minute glands at the base of the lobes; 

 corolla rotate, deeply 5-parted, the lobes reflexed in anthesis; hoods of the crown of 

 various shapes, not narrowed below, bearing hornlike processes within the hood; 

 anther wings broader below the middle; stigma 5-angled, fiat-topped; follicles mostly 

 smooth; seeds comose. 



key to the species. 

 Leaves linear or filiform. 



Hoods 3 times as long as the anthers, acute, recurved; stems 

 much branched, puberulent throughout; leaves 



nearly filiform 1. A. inacrotis. 



Hoods slightly if at all longer than the anthers, toothed or 

 obtuse, erect; stems simple or sparingly branched, 

 glabrous or nearly so; leaves broader. 



Hoods 5-toothed 2. A. quinquedentata. 



Hoods entire. 



Leaves scattered, rigid; plants 10 to 20 cm. high. . . 3. A. pumila. 

 Leaves opposite or verticillate, weak; plants 40 to 



60 cm. high or more 4. A. galioides. 



Leaves lanceolate or broader. 



Leaves narrowly lanceolate to narrowly oblong, acute. 



Stems hirsute; corolla orange 5. A. tuherosa. 



Stems not hirsute; corolla never orange. 



Pedicels erect ii fruit; flowers bright purple; 

 yjlants tall, erect, 60 to 100 cm. high, nearly 

 simple 6. A. incarnata. 



