372 Gruenberg and Gies: Notes on "bastard" logwood 



metabolic tendencies in these logwoods are essentially the same, 

 varying only, perhaps, in the course of events which involve rela- 

 tively slight quantities of pigment. * 



Tinctorial differences. — The foregoing results having 

 shown that the differences among these logwoods were chiefly if 

 not solely tinctorial, we next endeavored to ascertain the extent of 

 the pigmentary variations. 



Our first experiments in this connection were efforts to deter- 

 mine the relative tinctorial intensity of extracts of different samples 

 of heart-wood sawdust made with equal volumes of various sol- 

 vents under similar conditions of temperature, shaking, etc., from 

 the same quantities of material dried to constant weight at iio° 

 C.f Among the samples were several inferior qualities of red 

 wood from dead and decaying trees. 



Table IV gives our first results in this connection. The fig- 

 ures in that table denote the relative positions in a series of ten 

 extracts — I indicating weakest coloration, 2 the pigmentation of 

 next higher intensity and so on to 10 showing the most decided 

 tinctorial effect. 



The shade of color varied with each extractant, as would be 

 expected. The following observations were made in this connec- 

 tion, on the color of the series of extracts referred to in table IV. 



I. Water — slight yellowish-brown to deep reddish-brown. J 

 II. o. 2 per cent. HC1 — faint yellow to orange. 

 III. 2.0 per cent. HC1 — faint yellow through reddish-brown to bright red. 

 IV. o.oi percent. KOH — chocolate coloration throughout. 

 V. 0.15 per cent. KOH — deep chocolate coloration throughout. 

 VI. 0.5 per cent. Na 2 CO s — chocolate coloration throughout; less than in V, 

 greater than in IV. 

 VII. Saturated borax solution — faint yellow to deep reddish-yellow. 

 VI 1 1. Ether — faint yellow to orange. 



IX. Absolute alcohol — faint yellow to red. 



X. Acetone — faint yellow through greenish-yellow to yellowish-red. 

 XI. Acetic ether — faint yellow to deep reddish-yellow ; brighter than in VII. 



* These conclusions are in harmony with those drawn from other standpoints by 

 Professor Earle (quoted on page 368). They were arrived at independently by us and 

 were included in our report, in December, 1902, to the Botanical Society of America, 

 before we were aware of Professor Earle's deductions. Science, II. 17 : 338. 1903. 



| Drying occurred rapidly and seemed to have no transforming effect on the dust. 

 This fact was noted before in another connection (page 369). 



J The coloration intensities are indicated progressively from 1 to 10 (see table 

 IV). Individual exceptions are not referred to. 



