508 CONTEIBUTIONS FROM THE NATIONAL HERBAEIUM. 



1. PhiliberteUa crispa (Benth.) Vail, Bull. Torrey Club 24: 306. 1897. 

 Sarcostemma crispum Benth. PI. Hartw. 291. 1841. 



Sarcostemma undulata Torr. U. S. & Mex. Bound. Bot. 161. 1859. 

 Philibertia undulata A. Gray, Proc. Amer. Acad. 12: 95. 1876. 

 Type locality: Aguas Calientes, Mexico. 

 Range: Western Texas to New Mexico and southward. 



New Mexico: Lone Pine; Deming; Organ Mountains; Queen. Rocky hillsides 

 and canyons, in the Lower and Upper Sonoran zones. 



2. PhiliberteUa cynanchoides (Decaisne) Vail, Bull. Torrey Club 24: 307. 1897. 

 Sarcostemma cynanchoides Decaisne in DC. Prodr. 8: 540. 1844. 



Philibertia cynanchoides A. Gray, Proc. Amer. Acad. 12: 64. 1876. 

 Type locality: Mexico. 

 Range: Utah and Arizona to western Texas. 



New Mexico: Mountainswestof San Antonio; Kingston; Mesilla Valley; Tularosa; 

 Roswell. Mesas and low hills, in the Lower Sonoran Zone. 



3. PhiliberteUa heterophyUa (Engelm.) CockereU, Bot. Gaz. 26: 279. 1890. 

 Sarcostemma heterophyUa Engelm. in Torr. U. S. Rep. Expl. Misa. Pacif. 5: 362. 1856. 

 Philibertia linearis heterophyUa A. Gray, Syn. Fl. 2': 88. 1878. 



Type locality: Near Fort Yuma, Arizona. 



Range: Southern California to western Texas and adjacent Mexico. 

 New Mexico: Mesa west of Organ Mountains; Organ Mountains; Knowles. Dry 

 hills and mesas, in the Lower Sonoran Zone. 



3. ASCLEPIODORA A. Gray. Antelope horns.' 



Erect or spreading perennial herb, sparingly pubescent, with several stout ascending 

 stems from a woody root; leaves alternate, elongate-lanceolate, short-petiolate; flowers 

 rather large; calyx lobes narrowed, acute; corolla rotate, the lobes broadly ovate, 

 green, spreading in anthesis; hoods inserted over the whorl of the short column, dark 

 purple, obtuse, crested within; anther wings salient above the middle; follicles large, 

 about 8 cm. long, erect, on recurved pedicels. 



1. Asclepiodora decumbens (Nutt.) A. Gray, Proc. Amer. Acad. 12: 66. 1876. 



Anantherix decumbens Nutt. Trans. Amer. Phil. Soc. n. ser. 5: 201. 1837. 



Acerates decumbens Decaisne in DC. Prodr. 8: 521. 1844. 



Type locality: "On dry hills near the confluence of Kiamesha and Red riA^er." 



Range: Arkansas and Texas to Utah and Arizona. 



New Mexico: Tunitcha Mountains; Carrizo Mountains; Dulce; Sierra Grande; 

 west of Santa Fe; Las Vegas; Magdalena Mountains; Kingston; Organ Mountains; 

 Gray; Cloudcroft; White Mountains. Plains and hills, in the Lower and Upper So- 

 noran zones. 



4. ACERATES Ell. 



Erect perennial herbs 80 cm. high or less, with opposite or alternate leaves, the flow- 

 ers in lateral axillary umbels on short peduncles; horns of the hoods wanting or very 

 obscure; anther wings angled near the middle; otherwise like Asclepias. 



key to the species. 

 Leaves linear. 



Hoods truncate at the apex, with an obscure horn within 3. A. rusbyi. 



Hoods emarginate, crestless within 4. A. auriculata. 



Leaves not linear. 



Leaves oblong; anther wings gradually narrowed below 1. A. viridiflora. 



Leaves elongated-lanceolate; anther wings abruptly narrowed 



below 2. A. ivesii. 



' A translation of the very appropriate Navaho name, referring to the form of the 

 pods. 



