WOOTON AND STANDLEY—FLORA OF NEW MEXICO. 511 
A common weed in cultivated fields and along irrigating ditches. Our specimens 
may include A. verticillata, but we have been unable to separate them definitely. 
They also include specimens cited by various authors as A. subverticillata. In our 
opinion there is only one species of this type in New Mexico. 
5. Asclepias tuberosa L. Sp. Pl. 217. 1753. BUTTERFLY WEED. 
Type Locatity: ‘‘Habitat in America boreali.’’ 
Rance: British America to Florida, Texas, and Arizona. 
New Mexso: Santa Fe and Las Vegas mountains; Sandia Mountains; Kingston; 
Mogollon Mountains; Burro Mountains; San Luis Mountains; Capitan Mountains; 
White and Sacramento mountains. Transition Zone. 
The western form is variable and somewhat different from the typical eastern one. 
It has usually narrower, more crowded leaves and often paler flowers. In the higher 
mountains the flowers are darker and as brightly colored as in the eastern plants. 
6. Asclepias incarnata L. Sp. Pl. 215. 1753. SWAMP MILKWEED. 
Asclepias incarnata longifolia A. Gray, Syn. Fl. 21: 91, 1878. 
TypE Locauity: ‘‘Habitat in Canada, Virginia.”’ 
Rance: British America to New Mexico and Florida. 
New Mexico: White and Sacramento mountains; Roswell. Wet ground, in the 
Upper Sonoran and Transition zones. 
The subspecies proposed by Doctor Gray does not seem to deserve a name. Our 
plants have the leaves narrow, but not more so than some of the eastern ones. 
7. Asclepias involucrata Engelm. in Torr. U. 8. & Mex. Bound. Bot. 163. 1859. 
Type Locauity: Sandy soil, on the Mimbres and near the Copper Mines, New Mex- 
ico. Type, Mexican Boundary Survey no. 1074. 
RanGE: Southern Utah to Arizona and New Mexico. 
New Mexico: Farmington; Sierra Grande; Nara Visa; Santa Fe Creek; Las Vegas; 
Mogollon Creek; San Augustine Plains; Santa Rita. Dry hills and plains, in the 
Upper Sonoran Zone. 
8. Asclepias brachystephana Engelm. in Torr. U. 8. & Mex. Bound. Bot. 163. 
1859. 
Tyre Locairy: ‘“‘Sandy soils, valley of the upper Rio Grande, Chihuahua, and 
Sonora.”’ 
Rance: Wyoming to Arizona and Texas and southward. 
New Mexico: Socorro; Hillsboro; Organ Mountains; Chosa Spring; Roswell; Carls- 
bad. Sandy plains, in the Lower Sonoran Zone. 
9. Asclepias uncialis Greene, Bot. Gaz. 5: 64. 1880. 
Type Locauity: Open hilltops in southwestern New Mexico, about Silver City. 
Type collected by E. L. Greene. 
Rance: Wyoming to Arizona and New Mexico, 
New Mexico: Silver City. 
10. Asclepias speciosa Torr. Ann. Lyc. N. Y. 2: 218. 1828. 
Type Locauity: ‘‘On the Canadian?,” Colorado or New Mexico. 
Rance: British Columbia and Manitoba to California and New Mexico. 
New Mexico: Farmington; Shiprock; Chama; Perico Creek; Pecos; Las Vegas; 
Joseph; Middle Fork of the Gila; White and Sacramento mountains. River valleys 
and wet ground, in the Upper Sonoran and Transition zones. 
11. Asclepias nummularia Torr. U.S. & Mex. Bound. Bot. 163. pl. 45. 1859. 
Type LocaLiry: Copper Mines, New Mexico. Type, Mexican Boundary Survey 
no. 1073. 
RanGE: Southern New Mexico and Arizona and southward. 
New Mexico: San Luis Mountains; Dog Spring; Santa Rita. Dry hills and mesas, 
in the Lower Sonoran Zone, 
