508 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
1. Philibertella crispa (Benth.) Vail, Bull. Torrey Club 24: 306. 1897. 
Sarcostemma crispum Benth. Pl. Hartw. 291. 1841. 
Sarcostemma undulata Torr. U. 8. & Mex. Bound. Bot. 161. 1859. 
Philibertia undulata A. Gray, Proc. Amer, Acad, 12: 95. 1876. 
Type Locauity: Aguas Calientes, Mexico. 
Ranae: 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. Philibertella 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. 
Rance: Utah and Arizona to western Texas. 
New Mexico: Mountains west of San Antonio; Kingston; Mesilla Valley; Tularosa; 
Roswell. Mesas and low hills, in the Lower Sonoran Zone. 
8. Philibertella heterophylla (Engelm.) Cockerell, Bot. Gaz. 26: 279. 1890. 
Sarcostemma heterophylla Engelm. in Torr. U. 8. Rep. Expl. Miss. Pacif. 5: 362. 1856. 
Philibertia linearis heterophylla A. Gray, Syn. Fl. 21: 88. 1878. 
Type Locauiry: Near Fort Yuma, Arizona. 
Rane@e: 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. 
Tyre Locauity: ‘On dry hills near the confluence of Kiamesha and Red river.”’ 
Rance: 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. rusbyt. 
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.............- wc eee ee eee eee eee eee eee eee eee 2. A. wesit. 
1 A translation of the very appropriate Navaho name, referring to the form of the 
pods. 
