E. R. Speyer 129 



SECTION II. 



EXPERIMENTS WITH THE DECOMPOSITION PRODUCTS OE BANANA 

 AM) SUBSTANCES ALLIED TO THEM. 



It is possible to deduce the approximate composition of banana 

 from E. Munroe Bailey's "Studies on the Banana," Journal of Biological 

 Chemistry, i. 1, p. 355. 



Ripe Banana. 



Water difference from 100. 



When invert high, cane low and vice versa. 



Unripe Banana. 



Unripe banana contains insoluble carbohydrates, which, in the- 

 presence of air, give place to soluble carbohydrates when the fruit 

 ripens. 



Thus the proportion of soluble and insoluble carbohydrates as 



dextrose is 



Soluble Insoluble Total 



In unripe banana 1-3 25-2 26-5 



In ripe banana 17-1 1-9 19 



The decomposition products therefore contain few nitrogen com- 

 pounds, and ferment to the decomposition products of carbohydrates, 

 such as alcohols, acids and their compounds. 



The method of experiment adopted was similar to that in Section I, 

 but the traps were placed in a glass house on a table 4 feet from the 

 ground and in a straight line. Instead of employing control substances, 

 each pair of traps was baited with a known quantity of the same sub- 

 stance. 



The distance between each pair of traps was about 4 feet, those 

 containing similar substances being placed 6 inches apart. The pairs 

 were interposed as in the previous experiments. 



The first series was carried out to determine the general qualities 

 of carbohydrates in an unfermenting condition. For the purpose, brown 

 sugar, white sugar, and starch were used in a dry condition; water was 



Ann. Biol, vn 9 



