120 



redissolved with higher temperatures, lu the past summer soire difficulty 

 was experienced with it in preserving larger fishes in warm weather. 

 A sample of the formalin was submitted to Dr. Palmer, Professor of 

 Chemistry in the University of Illinois, for examination. The following is 

 his report on it: "We find that it contains 38I2 per cent, of formic alde- 

 hyde. This is practically the quantity that is supposed to be contained in 

 commercial formalin, i. e., 40 per cent, formic aldehyde. I find that nearly 

 one-half of the foi*mic aldehyde is polymerized, i. e., about 18^ per cent. 

 is in the form of the polymer tri-oxymethylene. I am not sufficiently 

 familiar with the use of the formalin as a preservative to be able to 

 state whether this polymerization will interfere with the use of the 

 formalin as a preservative, but would suggest that possibly the formalin 

 has proved unserviceable because nearly half of the constituent which 

 is expected to do the worli is in the form of the polymer, and probably 

 unserviceable." 



Notes ox the Examination of A^egetaele Powders. 

 By John S. Wright. 



'.Abstract.l 



Brief accounts were given of the methods employed in preparing 

 vegetable powders for microscopical studies, especially through the use 

 of clearing and other microchemical reagents. References were made 

 to the work previously done along this line and to the literature of the 

 subject. Histological characters of vegetable powders were discussed, 

 particular attention being paid to the value of the microscope as a means 

 of identifying and detecting adulterations in granulated and powdered 

 drugs and spices. 



The Staining of Vegetable Powders. 

 By John S. Wright. 



[Abstract.] 

 The use of differential stains to aid in the study of the histological 

 elements of vegetable powders is in many instances important. If in 



