In this thesis I propose to deal with the so-called solitary abscess of the liver as it occurs in the tropics, and not with hepatic abscesses due to pyaemia, or secondary septic infections from other foci of disease, such as may occur following appendicular abscess, or other lesions in the stomach, bowel, gall-bladder or pelvis. Nor do I include abscesses following an injury to the liver, or in connection with hydatid disease. An experience of general practice in the Straits Settlements, extending over twelve years, goes to prove that liver abscess is fairly common in that part of the world, though Scheube (1) says that "a few tropical regions such as Singapore are free of it". During the last twelve years I have had fifteen cases of liver abscess under my care in Penang, which has a European population of about five hundred and a native population of over ninety thousand, of whom only a small proportion have adopted European methods of treatment. The average annual admission rate of such cases to the General Hospital, Penang, has been from three to five cases, whilst in Singapore with a population of about a hundred and fifty thousand, from twelve to fifteen cases have been admitted yearly to the General Hospital there. These figures do not include cases occurring in the troops which are treated in the military hospitals, nor cases admitted to the Pauper Hospital, Penang or to the Tan LTock Seng Hospital, Singapore, A certain number of cases undoubtedly occur amongst the Chinese and other natives, who are treated by their own doctors and priests. Cases of liver abscess are also not uncommon amongst the planters in the Federated Malay States, and, these caseshave been more frequent during the last four or five years, since the enormous spread of the rubber-growing industry has attracted to the country a rapidly increasing number of Europeans of an age between twenty and forty-five, which seems to be the most favourable time for the development of this disease. This is not to be wondered at, when one considers that the conditions of a planter's life are such as to expose him to greater risks from sun-stroke, from chills either after perspiring profusely, or after being soaked with rain, and from drinking contaminated water, than fall to the lot of the dweller in towns where the water supply is good, and where there is no necessity for one to-be exposed either to the sun or to rain.