388 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
1. Koeberlinia spinosa Zucc. Abh. Akad. Wiss. Miinchen 1: 358. 1832. 
TYPE LocaLity: Mexico. 
Range: Southern New Mexico and Arizona, western Texas, and adjacent Mexico. 
New Mexico: Warm Spring; plains south of the White Sands; west of Dona Ana 
Mountains; Black Range; Hachita; Organ Mountains; north of Deming. Dry plains 
and hills, in the Lower Sonoran Zone. 
_ A very spiny, much branched shrub, usually branched from the base, but some- 
times with a definite trunk. It is sometimes called ‘‘crown of thorns.” 
76. MALPIGHIACEAE. Malpighia Family. 
1. JANUSIA A. Juss. 
Low twining perennial with woody stems; leaves opposite, narrowly lanceolate, 
1 to 3. cm, long, pubescent on both surfaces; sepals 5; petals 5, yellow, turning reddish 
brown; stamens 5; styles united; fruit a samara, 9 to 12 mm. long. . 
1. Janusia gracilis A. Gray, Pl. Wright. 1: 37. 1852. 
TYPE LOCALITY: Mountains east of El Paso, Texas. 
Rance: Western Texas to southern Arizona and adjacent Mexico. 
New Mexico: Parkers Well; Tortugas Mountain. Dry hills, in the Lower Sonoran 
Zone. 
77. RUTACEAE. Rue Family. 
Aromatic shrubs or low herbaceous perennials; leaves alternate, simple or com- 
pound, glandular-punctate; flowers perfect or by abortion polygamous, in cymes 
or short raceme-like clusters, not conspicuous; sepals 4 or 5, small; petals of the same 
number, dull-colored, small; stamens of the same or twice the same number, inserted 
on a hypogynous disk; pistil of 2 or 3 united carpels; fruit a capsule or samara. 
KEY TO THE GENERA. 
Low herbaceous plants; leaves small, simple........... 1. Rutosma (p. 388). 
Shrubs; leaves 3 to 10-foliolate, with large leaflets. 
Fruit a circular samara; leaves 3-foliolate. ........ 2. PrELEA (p. 388). 
Fruit a 2-celled pod without wings; leaves pal- 
mately 5 to 10-foliolate...............2.2--- 3. ASTROPHYLLUM (p. 390). 
1. RUTOSMA A. Gray. 
Perennial herb, 30 cm. high or Jess, with small linear sessile leaves and inconspic- 
uous flowers; fruit of 2 divergent carpels. 
1. Rutosma purpurea Woot. & Standl. Contr. U. S. Nat. Herb. 16: 143. 1913. 
Type Locauity: On an arid rocky slope at Bishops Cap at the south end of the 
Organ Mountains, New Mexico. Type collected by Wooton, March 30, 1905. 
RANGE: Western Texas to southern Arizona, 
New Mexico: San Andreas Mountains; Organ Mountains; Carrizalillo Mountains; 
south of Hillsboro; Mangas Springs. Dry rocky hills, in the Lower and Upper Sonoran 
zones. 
2. PTELEA 1, SHrupBy TREFOIL. 
Branching shrubs, 2 to 3-meters high, with smooth dark-colored bark on the old 
stems and greenish or yellow or reddish brown bark on the young stems, strongly 
scented; leaves 3-foliolate, the leaflets oblong-lanceolate or rhombic, the terminal 
one attenuate at the base, the lateral ones inequilateral, pellucid-punctate; flowers 
polygamous, greenish yellow, small, cymose; sepals, petals, and stamens 4 or 5, the 
last abortive in the pistillate flowers; ovary 2 or 3-celled; fruit a flattened, 2 or 
3-seeded, disk-shaped, reticulate samara, 
