As might be anticipated, fibrinous formations, while of small size, are sometimes washed away from their attachments and swept on with the current of blood into the arteries and carried to distant parts of the body, as is sometimes the case also in aneurism, thus producing the embolic masses often found blocking up arteries in different parts of the body. When upon the right side, the embolus would be carried into the pulmonary artery, obstructing the circulation through the lungs, and producing symptoms more or less grave, according to the size of the clot. Upon the left side of the heart, from the greater force of the circulation, these bodies are probably more frequently swept away from their attachments and carried into the aorta, and thus on, perhaps, through the carotids to the head, or into the subclavian, or down the aorta, finally lodging in some of the branches of the lower extremities. Convulsions, paralysis, etc., are not unfrequently produced by the lodgment of emboli in some of the arteries of the brain, while, when carried into the arteries of the extremities, pain, falling of temperature, impairment of sensation, contraction of muscles, atrophy, and even gangrene may result. The following examples will serve to illustrate the class of cases to which I refer: CASE I.—_Death from Heart Clot in Anæmia._ A lad, 11 years old, and very anæmic, went to school in the morning in his usual health; while there was taken with a chill. On his way home vomited freely. The chill lasted for a long time, and was accompanied with an oppression in breathing, which gradually increased through the day and night, and until the time of my first visit at 11 o’clock A. M. the next day. I then found him extremely pallid, lips bloodless, perspiring freely, suffering from great restlessness and distress, with extreme dyspnœa; mind wandering, pulse irregular and feeble; action of the heart very tumultuous, the normal sounds being unrecognizable. In the neck noticed a rapid rolling pulsation of the jugulars, which presented two beats to one of the artery at the wrist. At my second visit, made at 4 o’clock P. M., the patient had just expired. The autopsy, made twenty hours after death, gave the following results: Upon opening the abdomen found the liver presenting a dark mottled appearance, and highly congested; other abdominal organs natural; pericardium contained about one ounce of serum. Upon opening the right auricle of the heart, found a firm fibrinous mass, extending downwards through the ventricular opening, and which, upon the latter cavity being opened, was found firmly attached to the tricuspid valves, and entangled with the fleshy columns and tendinous cords.