The X-ray method lends itself less successfully to the study of deglutition in man than in the other animals we have studied. The thickness of the thorax, the distance of the œsophagus from the surface, and the relation to dense tissues render the observation of a swallowed mass difficult, especially when the mass is in rather rapid motion. The few observations which we have to report were made on a seven-year-old girl, placed in the sitting posture. Gelatine capsules containing bismuth were used for solids, and were traced to a point below the heart. The motion was very regular, and apparently due to peristalsis, for the bolus descended without a hitch or irregularity of any kind. Sometimes the capsule became fixed in the upper œsophagus, at about the level of the second rib. Repeated swallows of water would fail to dislodge it. An interesting point was noted here. With each attempt at swallowing, the capsule would rise slightly, as if the œsophagus was pulled up with the rise of the larynx; then the capsule would descend to its former position. Semi-solids--a mush of bread and milk--could be seen about as far as solids; that is, to just below the heart. The motion of the mushy bolus was the same as with solids, except that the rapidity was perhaps slightly greater. It should be noted here that with the human subject, as well as with the horse, our results for semi-solids differ from those derived by Meltzer’s method; for according to his statements semi-solids, like liquids, are squirted down the œsophagus, and are not propelled by peristalsis, as has been the case in our observations. Liquids--bismuth and water--were seen only in the neck and upper thorax. Here there was a decided squirt. With the rise of the larynx the liquid was seen to pass rapidly through the pharynx and well down into the thoracic œsophagus before it was lost to observation. The rate, however, by estimation was less than that of liquids in the horse.