The question of the causation of typhoid fever by oysters is one of great importance, and one that should be clearly understood by everyone. That oysters are one of the means by which some recent epidemics of typhoid fever have been spread is undoubted, but the exact part that they have played is not so easy to understand, for the latest commission upon the question found that the typhoid bacillus is killed by immersion in sea-water, that it did not occur in any oysters that they opened, and when it was injected into the oyster, it was promptly killed. This seems to say emphatically that oysters cannot harbour the typhoid bacillus, and therefore cannot produce typhoid fever. But medicine is not as easy as that. That the oysters they examined could not produce typhoid fever is certain, but their remarks do not by any means prove that typhoid is not spread by any oysters. At one time there was very great excitement about this question, and a tremendous lot of nonsense was talked about it. Some persons maintained the typhoid bacillus only occurred in bad oysters. We suppose a bad oyster is eaten occasionally, but Lord X.’s guests are not likely to be troubled with bad oysters. Oysters cannot cause typhoid fever unless they contain this bacillus, and they only obtain it from sewers opening into the sea. Therefore it is only those oysters which have come from places where sewers open into the sea that can cause typhoid fever. Of course, as soon as the oyster scare was started, everybody who caught typhoid fever attributed it to oysters she had eaten the day, the week, month, or year before. But the incubation period of typhoid fever is from one to three weeks; that means that when the bacilli get into the body they do not produce the disease till from one to three weeks after infection. Therefore it is only oysters eaten from one to three weeks before the onset of the fever that could possibly have caused the disease. As a matter of fact, oysters are a real, but not very common, method by which typhoid is spread. We notice that one of the three guests who have taken oysters discards one because it is green. He is quite right to do so, for though it may be quite wholesome, it may be coloured with copper. Doubtless it would do no harm, but he is quite right not to risk the possibility of sickness for an oyster! Amongst the other items of the luncheon we notice cold beef and salad. These will furnish us with material for discussion, for there are several very important medical points in connection with both.