Summary and Conclusions 1. A brief resume is given of published work relative to early lesions in amebiasis. Three tables from the work of Deschiens (1938) are consolidated into table 1 herein. 2. Experimental work conducted by the authors is presented. An attempt is made to determine the influence of certain accessory factors in the initial penetration of the colonic mucosa by E. histolytica. Croton oil irritation and bacteria derived from one of our amebic stool cultures show definitely the effect of accessory aids to penetration or positive invasiveness by E. histolytica of the colonic mucosa of cats as well as kittens. 3. The fact that it was easily possible to obtain amebic infections in adult cats of any weight with certain strains of E. histolytica in conjunction with suitable predisposing agents is something which should contribute materially to the study of host resistance and natural immunity in amebiasis. 4. The results obtained by the authors are not in accord with those reported by Meleney and Frye and Faust and Schwartzwelder but are in agreement with those of Deschiens and Decort and afford evidence supporting the plausibility of Westphal's conclusion regarding the outcome of his interesting self-imposed experiment.