PERKINS THE LEGUMINOSAE OF PORTO RICO. 173 



cm. long by about half as broad, the Jateral ones opposite, short-stalked, both sides 

 subglaucous and thinly silvery, the upper nearly or quite glabrous when mature, turn- 

 ing blackish when dried; racemes moderately dense, 2.5 to 5 cm. long when in flower, 

 nearly sessile; pedicel equaling the obliquely campanulate, thinly silvery calyx, 

 which is not more than 1 mm. deep, the lower teeth lanceolate, reaching half way down, 

 the upper shorter; corolla fugacious, yellow, 3 to 4.5 mm. long. Pod reflexed, sickle- 

 shaped, 1 to 2 cm. long, 3 mm. thick, subtetragonous with thickened sutures, glabrous 

 when mature, 6 to 8 seeded. 



Near Bayamon in cultivated localities; Sierra de Naguabo, near Rio Blanco; near 

 Yabucoa in the coast districts; near Patillas on the sea at Guardaraya; near Coamo, in 

 meadows between Serillos and Salinas; near Adjuntas on declivities at Saltillo; near 

 Guayanilla on calcareous mountains near Pefion; near Guanica, in fields at Punta de 

 los Pescadores and in coast districts near La Ballena; near Cabo Rojo in pastures; near 

 Mayaguez and Aflasco. Bahama, Cuba, Jamaica, Cayman (Hitchcock), Haiti, St. 

 Thomas, St. Croix, St. John, St. Bartholomew (Stockholm Herbarium), Guadeloupe, 

 Martinique, St. Vincent, Mustique, Bequia (Kew Bull. no. 81, p. 245), Barbados, 

 Grenada, Tobago, Trinidad (Grisebach), Margarita. It is said to be a native of tropical 

 America. 



Indigofera suffruticosa is much cultivated in the tropics and subtropics and from it is 

 prepared the well-known coloring matter, indigo. It is obtained in the following 

 manner. The plants are mowed just before the flowerirfg time and soaked in water 

 until the liquid becomes a deep yellowish-green color. The fluid is then drained into 

 large vessels or into a cistern, where it is brought, as much as possible, in contact with 

 the air, by means of wheels and shovels, in order that it may take up oxygen. The 

 indigo substance becomes blue and insoluble in water, and sinks to the bottom in the 

 form of a blue powder. This is strained out by woolen cloths and dried. Indigo finds 

 extensive use as a dyestuff, coloring cotton, wool, and silk dark blue. Mixed with oil, 

 it forms a paint of great body, but one that is easily decomposed by pure air. 



Local name, anil, indigo. 



2. Indigofera g-uatimalensis Moc\ & Sesse. 

 (Urban, 282.) 



Shrub, 1.5 meters high; branches woody, deeply sulcate, thinly silvery; stipules 

 small, setaceous; petiole about 1 cm. long, firm erecto-patent; leaves 4.5 to 6 cm. long; 

 leaflets 4 to 6 pairs, oblong or obovate, 1 to 2 cm. long, 5 mm. broad, the lateral ones 

 opposite, short-stal.ked, the upper one with a petiolule 5 mm. long, all clothed on both 

 sides with rather long gray hairs; racemes 1 to 1.5 cm. long, nearly sessile; pedicel about 

 1 mm. long; calyx pilose, 1 mm. deep; corolla 3 mm. long; pod erect, straight, subtet- 

 ragonous, pilose, 1 cm. long, 2 mm. wide, with thickened sutures, 3 or 4-seeded. 



Near Cabo Rojo in pastures; near Mayaguez, on hills toward Boquillas; near Rincon 

 on declivities at Calvache. Cuba (cultivated, Prain and Baker), St. Thomas, Mar- 

 tinique (introduced), Guatemala (Prain and Baker), Venezuela, Ecuador (Prain and 

 Baker), Peru. 



This plant differs from /. suffruticosa in having thick pods which are smaller and 

 fewer-seeded. 



30. DALEA L. 



Dalea Juss. Gen. 355. 1789, not P. Br. 1756. 

 Parosela Cav. Desc. 185. 1802. 



Calyx 5-cleft or 5-toothed, often glandular; the segments subequal; petals unguicu- 

 late, the claws of the wings and keel united with the stamen-tube to the middle, decid- 

 uous by an articulation; standard free, inserted at the bottom of the calyx, the limb 

 cordate; stamens 10 (rarely 9) monadelphous, the tube cleft; ovary sessile or- shortly 



