This insect has been mentioned several times in entomological literature. The first reference to its bite probably was made by Townend Glover in the Annual Report of the Commissioner of Agriculture for 1875 (page 130). In Maryland, he states, _M. picipes_ is found under stones, moss, logs of wood, etc., and is capable of inflicting a severe wound with its rostrum or piercer. In 1888 Dr. Lintner, in his Fourth Report as State Entomologist of New York (page 110), quotes from a correspondent in Natchez, Miss., concerning this insect: "I send a specimen of a fly not known to us here. A few days ago it punctured the finger of my wife, inflicting a painful sting. The swelling was rapid, and for several days the wound was quite annoying." Until recent years this insect has not been known to the writer as occurring in houses with any degree of frequency. In May, 1895, however, I received a specimen from an esteemed correspondent--Dr. J. M. Shaffer, of Keokuk, Iowa--together with a letter written on May 7th, in which the statement was made that four specimens flew into his window the night before. The insect, therefore, is attracted to light or is becoming attracted to light, is a night-flier, and enters houses through open windows. Among the several cases coming under the writer's observation of bites by this insect, one has been reported by the well-known entomologist Mr. Charles Dury, of Cincinnati, Ohio, in which this species (_M. picipes_) bit a man on the back of the hand, making a bad sore. In another case, where the insect was brought for our determination and proved to be this species, the bite was upon the cheek, and the swelling was said to be great, but with little pain. In a third case, occurring at Holland, S. C., the symptoms were more serious. The patient was bitten upon the end of the middle finger, and stated that the first paroxysm of pain was about like that resulting from a hornet or a bee sting, but almost immediately it grew ten times more painful, with a feeling of weakness followed by vomiting. The pain was felt to shoot up the arm to the under jaw, and the sickness lasted for a number of days. A fourth case, at Fort Bliss, Texas, is interesting as having occurred in bed. The patient was bitten on the hand, with very painful results and bad swelling.