WOOTON AND STANDLEY FLORA OF NEW MEXICO. 511 



A common weed in cultivated fields and along irrigating ditches. Our specimens 

 may include A. vcrticillata, 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. PI. 217. 1753. Butterfly weed. 

 Type locality: "Habitat in America boreali." 



Range: British America to Florida, Texas, and Arizona. 



New Mexico: Santa Fe and Las A^egas 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. PI. 215. 1753. Swamp milkweed. 

 Asclepias incarnata longifolia A. Gray, Syn. Fl. 2 1 : 91. 1878. 



Type locality: 'Habitat in Canada, Virginia." 



Range: 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. S. & Mex. Bound. Bot. 163. 1859. 

 Type locality: 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 

 Dpper Sonoran Zone. 



8. Asclepias brachystephana Engelm. in Torr. U. S. & Mex. Bound. Bot. 163. 



1859. 



Type locality: "Sandy soils, valley of the upper Rio Grande, Chihuahua, and 

 Sonora." 



Range: 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 locality: Open hilltops in southwestern Now Mexico, about Silver City. 

 Type collected by E. L. Greene. 



Range: Wyoming to Arizona and New Mexico. 

 New M bxico: Silver City. 



10. Asclepias speciosa Torr. Ann. Lye. N. Y. 2: 218. 1828. 



Ti pe i ocality: "On the Canadian?, " Colorado or New Mexico. 



Range: British. Columbia and Manitoba to California and Now Mexico. 



New Mexico: Farmington; Shiprock; Chama; Periio Creek; Pecos; Las Vegas; 

 Joseph; Middle Fork of the Gila; White and Sacramento mountains. River valleys 

 and wel ground, in the Upper Sonoran and Transition zones. 



11. Asclepias nummulaiia Torr. I . S. <V Mex. Bound. Bot. L63. /'/. 45. 1859. 

 Type locality: Copper Minos, Now Mexico. Type, Mexican Boundary Survey 



no. L073 



Range: Southern New Mexico and Arizona and southward 



New Mexico: San Luis Mountains; Dog Spring; Santa Rita. l>ry hills and ines;us, 

 in the Lower Sonoran Zone. 



