292 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1915. 



develops into a large 1-seeded orbicular indehiscent pod siirroimded 

 by a broad, rigid membranous wing with the point on one side or 

 turned toward the base. The tree yielding the Philippine lignum 

 nephriticum may be described as follows : 



Pterocarpus indicus Willcl. Sp. PL 3: 904. 1800; Prain, Indian Forestry 26, 



Append. 9: 7. 1900. 

 Pterocarpus pallidus Blanco, Flora Filip. 560. 1837. 



A large forest tree with a trunk often provided with broad but- 

 tresses with drooping branches. Leaves 8 to 10 inches long, com- 

 posed of 5 to 9 usually alternate leaflets ; these 2 to 4 inches long and 

 1^ to 2 inches wide, the terminal one usually the largest, ovate with 

 rounded, rarely tapering base and rounded, abruptly and obtusely 

 acuminate apex, the main nerves hardly more" prominent than the 

 secondary beneath. Inflorescence composed of lax panicles, little 

 branched, all except the endmost one issuing from the axils of leaves, 

 peduncle long, rachis and pedicels glabrescent ; pedicels three-tenths 

 of an inch long with two linear caducous bracteoles at the jointed 

 apex. Flowers yellow, corolla papilionaceous, twice as long as the 

 calyx, the standard and wings frilled on the margins. Pod orbicular 

 broadly winged, borne on a stipe three-tenths of an inch long, the 

 style on one side, some distance from the base, the margin of the 

 wing between the stipe and the style convex. 



Plate 6 is reproduced from a photograph of a specimen of Ptero- 

 carpus indicus in the United States National Herbarium, together 

 with a piece of the wood from which the cup shown in plate 1 was 

 turned. 



This species, which is endemic in the Philippines and the Malay 

 Archipelago, has been introduced as a shade tree in many localities 

 in the tropics. According to Major Prain, it does not occur spon- 

 taneously either in India or Burma, but it has been confused with 

 the well-known padouk {Pterocarpus macrocarpus Kurz) which is 

 endemic in the vicinity of Mandalay and in other parts of Burma. It 

 is interesting to note that the wood of the Burman padouk varies in 

 color very much like that of the Philippine narra, and it is impos- 

 sible in the forest to distinguish a tree yielding red padouk from one 

 yielding yellow or pale-colored wood. 



The genus Pterocarpus, as Prain has pointed out, is an exceed- 

 ingly important one. In addition to the narra and padouk already 

 mentioned, it includes the trees that yield the gum kino of commerce 

 {Pterocarpus marsupium Eoxb.), endemic in India and Ceylon; the 

 red Sanders {Pterocarpus santalinus L.), a much smaller tree of 

 southern India, usually with 3-foliolate leaves; and the Andaman 

 vermilion, or redwood {Pterocarpus dalhergioides Roxb.), which 



