I have memoranda of 218 cases in which I have given chloroform in operations for fistula _in ano_. In many of the cases the sinuses were very numerous and extensive. It is necessary that the patient should be quite insensible during this operation, to prevent the possibility of his moving suddenly whilst the bistoury is being used. _Operations on Ovarian Tumours._ I have notes of three cases in which I gave chloroform during the removal of an ovarian cyst. The first of these was in March 1850. Twenty-four pints of liquid were first evacuated from the tumour. It consisted of four cysts united together, two of which contained serous fluid of slightly different colour; the third contained serum tinged with blood, and the fourth and smallest cyst, a purulent fluid. An incision was made, twelve or fourteen inches in length, extending from the pubes to midway between the umbilicus and sternum. Some slender adhesions were removed at one spot. The tumour was attached by a membranous pedicle, with the left iliac fossa, and the fundus of the uterus. Needles were passed through the pedicle, and it was tied in three or four portions, when the tumour was removed. After the tumour was removed, the patient seemed to breathe entirely by the ribs, the diaphragm remaining relaxed, and not contracting, whilst the wound in the abdomen was being closed. Scarcely any blood was lost during the operation. The patient died of peritonitis early on the fourth day. The next case occurred on August 27th, 1850, and is reported in the _Medico-Chirurgical Transactions_ for 1851. Mr. Duffin was the operator, and the patient made a favourable recovery. The third operation was performed on the 31st of January, 1854. The patient was a spinster, twenty-eight years of age, and the tumour had not been tapped. It contained about two gallons of clear fluid, and was removed through an opening in the median line above the umbilicus, about seven inches in length. There was no depression when the patient awoke after the operation. She died within three days. I administered chloroform in two cases where it was intended to remove an ovarian cyst. In one case the cyst was so adherent to the peritoneum that it could not be removed; in the other case, there was no cyst, but some serum in the peritoneal cavity, and a tumour growing from the fundus of the uterus. This tumour was allowed to remain. Several medical men, in addition to the operator, had diagnosed an ovarian tumour in this case. These two patients recovered. I exhibited chloroform in four operations in which an ovarian cyst was opened, and the cut edges of it sewed to the wound in the abdominal parietes. These four patients, I believe, all died. I am quite certain as regards three of them.