52 



THE AMERICAN MUSEUM JOURNAL 



whirli the leaflets are not in the least 

 like those mentioned by this investi- 

 gator. 



The explanation of these ineongrui- 

 ties is qnite simple. Beyond donl)t, two 

 distinet woods have been called Ugiiiim 

 nephriticum: the diminntive Et/seit- 

 hardtia poJystachya and Rtcrocarpus 

 indicus, a giant tree of the Philippine 

 Archipelago and adjacent islands. The 

 first of these agrees perfectly with the 

 description of a plant with tiny leaflets 

 and spikes of small longish flowers, 

 while the second conforms to the ac- 

 count of the great logs larger than very 

 large trees. Moreover, the wood of 

 Eysenhardtia is so very like lignuni- 

 vitffi that Dragendorff,^ in the absence 

 of leaves and flowers, may well be ex- 

 cused for referring it to a species of 

 that tree; and, judging from its color 

 and texture, it seems very certain that 

 it was the wood with which the first 

 scientific experiments were performed. 

 Both the red palum indianmii and the 

 white wood from which the famous 

 Jesuit's cup was made may be included 

 in the second species, for all accounts 

 agree that of its wood there are two 

 varieties, one pale-colored, the other 

 reddish. In the Philippines, where the 

 tree is commonly called narra or naga. 

 the pale variety, which yields a fluores- 

 cence in a very marked manner, is 

 called "female" and the red variety, 

 possessing this characteristic in a less 

 degree, is called "male" narra. 



In connection with his work on the 

 economic botany of Mexico, the writer 

 has for years been seeking the source of 

 lignum nepliriticum. Among other 

 woods examined for the blue fluores- 

 cence characterizing this w^re specimens 

 of branches of E j/.^enha rdtia polystachya 

 collected by him in 190T in the vicinity 

 of Aguascalientes, the infusion of 

 which gave no evidence of fluorescence 

 in ordinary sunlight. From this fact 

 and from the circumstance that all 

 samples seen were either of shrubs or 



1 Dragendorff. Hril ,,fl,()iz<'n (p. 345). 1898. 



trees too small to yield wood for the 

 manufacture of bowls or cups, the writer 

 was inclined to agree with the opinion 

 that Eysenhardtia must be discarded as 

 a possible source of the magic wood. ]n 

 July, 1914, however, specimens of a 

 medicinal wood from Mexico were re- 

 ceived for identification, accompanied 

 by herbarium material from the same 

 tree. This proved to be Eysenhardtia 

 polystachya, known by the modern 

 Mexicans in many localities as palo 

 dulce, or "sweet wood." Its collector 

 had not noticed anything peculiar about 

 the color of its infusion, but dwelt upon 

 its efficacy as a cure for certain diseases 

 of fowls. The wood was a section of a 

 tree trunk, which, when deprived of its 

 Itark, was 7 cm. in diameter. Unlike 

 all other specimens of this wood seen 

 l)y the writer, it consisted chiefly of 

 dense straight-grained dark brown 

 heartwood, very much like lignum-vita:; 

 in appearance, surrounded by a ring of 

 brownish white sapwood from 5 to 8 

 mm. thick. 



A few small chips of the heartwood 

 in ordinary tap water tinged the latter 

 a golden yellow, which soon deepened to 

 orange and appeared like amber when 

 held between the eye and the window. 

 When the glass was held against a dark 

 background the liquid glowed with a 

 beautiful peacock fluorescence very 

 much like that seen in quinine. Placed 

 partly in a sunbeam, half of the liquid 

 appeared yellow and the other half 

 blue ; and when the sunlight was 

 focused upon it by the lens of a com- 

 mon reading glass, the vial seemed to 

 be filled with radiant gold penetrated 

 l)y a shaft of pure cobalt. 



There was no longer any doubt as to 

 the identity of the wood. This could be 

 only the Mexican lignum nephriticum 

 of previous experiments, and it was un- 

 doubtedly the wood of Eysenhardtia 

 polystachya. a tree with small pinnately 

 compound leaves and with spikes of 

 small flowers which, although originally 

 white, had turned velloAvish in drying. 



