Although the Carabidae or Ground Beetles are largely predaceous in habit, Forbes has shown by studying the contents of the intestine that certain species exhibit different feeding habits. Several questions may be asked regarding the feeding of ground beetles. What do the beetles eat, how do they attack, and how do the prey defend themselves? Is there a relation between the size of prey and the predator and finally is there any evidence of cannibalism? Since the observation of feeding in a natural environment is exceedingly difficult, caged specimens were used in my experiments and therefore the conclusions drawn may not be final in all cases.