212 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
KEY TO THE SPECIES. 
Three lowest joints of the loment usually not developing, 
twisted; loments sessile; tips of the calyx lobes 
subulate. 
Leaflets linear-lanceolate; terminal joint of the loment 
semiorbicular _~-_--_-_-_ 1. A. scopulorum. 
Leaflets lance-ovate; terminal joint of the loment ellip- 
tic-oblong, abruptly narrowed at both ends_______ 2. M. mollis. 
Only the lowest joint, or sometimes none, abortive, the joints 
not twisted; loments usually stipitate; tips of calyx 
lobes not subulate. 
Flowers and fruit in a dense panicle; often more than 
two joints of the loment developing___.__________ 3. M. skinneri. 
Flowers and fruit not in a dense panicle, the inflores 
cence open; never more than two joints of the 
loment developing. 
Leaflets orbicular, rounded at the apex_________ 4, M. painteri. 
Leaflets ovate or lanceolate, acute or acutish. 
Leaflets thick, glabrous, and shining above______ 5. M. metallica. 
Leaflets thin, pubescent, and dull above. 
Loments subsessile; leaflets with a broad, 
silvery stripe along the midrib_______ 6. M. albonitens. 
Loments conspicuously stipitate; leaflets not 
striped. 
Leaflets apiculate; joints very large, 
25 to 380 mm. long_____~~______ 7. M. lunata, 
Leaflets not apiculate; joints smaller, 
less than 20 mm. long. 
Joints narrowed at the base; leaf- 
lets lance-ovate _..._________ 8. M. angustata, 
Joints not narrowed at the base: 
leaflets ovate_______________ 9. AM. barclayi. 
1. Meibomia scopulorum (S. Wats.) Rose & Standley. Puare 51, b. 
Desmodium scopulorum S. Wats. Proc. Amer, Acad. 24: 47. 1889. 
Stems erect, slender, much branched, pale, minutely uncinate-ouberulent ; 
leaves trifoliolate; petioles slender, 30 to 85 mm. long, striate, puberulent ; 
leaflets linear-lanceolate, 55 to 80 mm. long, acute, rounded at the base, glabrous 
except along the minutely uncinate veins; stipules lanceolate, long-acuminate, 
persistent; petiolules 2 mm. long; inflorescence of terminal or axillary, slender 
panicles or racemes, the branches minutely puberulent: flowers solitary or in 
twos, on slender pedicels 10 mm. long; calyx teeth ovate, with subulate tips ; 
corolla not seen; bracts filiform, short; loments sessile, of usually 4 joints, all 
except the terminal one abortive, the lowest three twisted, densely puberulent ; 
terminal joint semiorbicular, 10 mm. long, with scarcely any suture on the 
upper edge, the walls thin, finely puberulent. 
Type locality, “Guaymas,” Sonora, Mexico. Type collected by Dr. Edward 
Palmer in 1887 (no. 258). 
Specimens examined: 
Sonora: On rocky ledges in the mountains about Guaymas, 1887, Palmer 
258, type collection. 
