The Influence of Soil Acidity on the pH Value of the Contents of the Digestive Tract of Japanese Beetle Larvæ.1

Abstract

In determinations of acidity within the digestive tract of insects it is important to know the fluctuations in pH brought about by variations in the acidity of the food taken in. In order to answer this question for larvæ of the Japanese beetle (Popillia japonica Newm.) specimens from soil plots varying in pH were dissected and tested for acidity by a potentiometer circuit (1)2 with a quinhydrone electrode (2).