44 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
atropurpureus and L. lanceolatus, and it is probable that L. hondurensis 
also belongs to the latter group. With these exceptions, Bentham’s 
species seem tolerably well grouped, but the same distinctions will 
hardly serve for the establishment of well-defined groups among the 
40 species recognized in this paper for Central America and Mexico. 
NEW CLASSIFICATION OF THE MIDDLE AMERICAN SPECIES. 
To provide for these species the following attempt has been made 
at a more comprehensive grouping, in sections and higher units. 
KEY TO THE SUBGROUPS. 
Legume narrowly lanceolate or broadly quadrate-lanceolate, the 
margin almost uniform in width, sharp-edged or rounded. 
(Subgenus 1. EULONCHOCARPUS. ) 
Costa and veins deeply impressed on the upper face of the 
leaflets, very prominent beneath; leaves more or less 
tomentose or villous; flowers (the standard princi- 
pally) more or less silky-pubescent; legume lanceolate 
or elongate, 1 to 6-seeded, glabrous or ferruginous- 
tomentose, (Series 1. IMpRESSINERVI.) 
Legume membranous, not over 2 cm. broad, more or less 
elongate; wings narrow, more or less distinctly 
plicate transversely on the vexillar side.......... 1, PHILENOPTERI. 
Legume coriaceous, ovate-lanceolate, the seeds em- 
bedded in a thick, porous tissue; wings ovate, 
not plicate; ovules 2 or 3................20 00 eee 2. SPONGOPTERI. 
Costa and veins seldom deeply impressed on the upper 
face of the leaflets, the veins more or less prominent 
beneath; leaves glabrous or more or less pubescent; 
flowers glabrous or pubescent; legume lanceolate or 
quadrate-lanceolate, 1 or 2-seeded, glabrous. (Series 2. 
PLANINERVI.) 
Leaflets punctate; calyx and petals often yellow-dotted; 
standard bilobulate at the base..................- 3. PuNcTATI. 
Leaflets not punctate and petals not dotted; standard 
elobulate, usually truncate at the base........... 4, EPuNCTATI. 
Legume lanceolate or elongate-linear, the vexillar margin thick- 
ened at the seeds, carinate or concave. (Subgenus 2, 
NEUROSCAPHA. ) 
Petals sparsely pubescent, or the standard silky-pubescent, 
the flowers then very small (not over 5.5 mm. long). 
Leaves rather small; legume (as far as known) glabrous, 
narrow and elongate, or broader and then 1-seeded 
(the leaflets then small). (Series 3. PuBIFLORI.) 
Petals more or less silky-pubescent. 
Leaves of medium size or large; legume thick, ferruginous- 
pubescent or glabrescent, sometimes glabrous. 
(Series 4. SzRICIFLORI.) 
Vexillar margin of the legume flat or concave....... 5. CONCAVI. 
Vexillar margin of the legume carinate........... ... 6. CARINATI. 
While still far from absolutely satisfactory, this arrangement seems 
to bring the species more closely together according to their nearest 
