7() 



toxylin is one of the most valuable of commercial dyes and the 

 l)usiness of supplying the wood from which it is made forms an 

 important industry in some of the West Indies. Considerable 

 annoj-ance has been caused by the fact that some of the logwood 

 or Hacuiatoxylon trees contain little or no dye, whole shipments 

 even having been condemned on this account. The so-called 

 " bastard logwood " is not always to be distinguished at the time 

 of cutting. It is either lighter in color or if dark at first it can 

 be recognized by not becoming still darker on seasoning for 

 some months as does the good wood. 



Professor Earle investigated the disease in the field and con- 

 cluded that the lack of pigment was not due to external condi- 

 tions, or to disease, or to immaturity, but that the logwood is a 

 variable plant and the bastard form is a variety or subspecies. 



The percentage of carbon in the ash-free material was deter- 

 mined for different samples with somewhat varying results but 

 showing that the good wood contains a slightly higher percen- 

 tage, due probably to the carbon in the pigment. 



Analysis of leaves, stems and roots of one-year-old plants 

 showed that the bastard plants contained slightly more ash and 

 water, but the difference was very slight. 



Extracts of the pigment were made with a number of different 

 solvents from varying samples of wood. The extracts with dif- 

 ferent solvents did not give parallel results as indicating the 

 amount of pigment. In dilutirig the extracts chemical changes 

 occurred. Alkalies increase the color of extracts of the good wood 

 but not extracts of the bastard wood. Acids have a parallel effect. 



Results on the soluble substances in the wood were not satis- 

 factory on account of decomposition on drying. There are prob- 

 ably several pigments. 



After a discussion of the paper the meeting adjourned. 



WiLLI.VM T. HORNE, 



Secretary pro fciii. 



NEw.s mars 



Dr. II. C. Cowles, of the University of Chicago, devoted a 

 large part of the month of April to field studies in plant ecology 

 in the vicinity of Miami, Florida. 



