(1) It is a matter of considerable interest that, with the exception of rat No. 1832, the rats were caught alive during a period when no rats with acute plague were found and when no human cases were occurring in the locality.

(2) It cannot be regarded merely as a coincidence that the lesions were in every instance situated within the abdomen. With our present knowledge it would be rash to speculate as to the method of infection in these cases, but it may be conceded that the most reasonable interpretation of the lesions involves the assumption of an intestinal infection.

(3) Examination after the animals were killed furnished no indication that their health suffered in any way; the organs were apparently normal and there was no emaciation.

(4) Although the number of cases is admittedly small and although it is difficult to estimate virulence with any degree of accuracy, yet it is noteworthy that of the animals inoculated directly from, and with subcultures of, these abscesses only one survived.