Leeches are common in the fountains and pools of Palestine, particularly in the northern parts, known to us familiarly as ‘Galilee,’ and further north in the district of the Lebanon. In the later summer and autumn months they are so plentiful in places that almost every horse and mule passing through these parts has a bleeding mouth. Under such conditions it is not wonderful that human beings from time to time are attacked. The domestic supplies of water are usually protected by the water-carrier's custom of straining it through a piece of fine muslin as he or she fills the pitcher. In some parts of the land the water at the source is kept free from leeches by means of fish; at Deishun, for example, a village in ‘Upper Galilee’ inhabited by Algerian settlers, the large stone tank into which the spring runs is full of a special fish—Capoëta fratercula, a kind of carp—which is there bred for the purpose and which is treasured by the inhabitants with superstitious reverence. Many of the springs in the mountains of Galilee and in the Lebanon are widely known for the multitude of leeches which lurk in their waters, but a thirsty traveller seldom has self-control enough to restrain himself from drinking, and when he does so, particularly at dusk or in the night, he is very likely to suck one in. It is stated in Allbutt and Rolleston's System of Medicine (2nd ed. Vol. II. Part II. p. 959) that the leech “remains in the stomach for a time and then begins to wander.” I have had a long experience of leeches as human parasites but have never seen nor heard of a case like this. The leech in every case I have met has attached itself to the mouth, throat, etc. in the process of swallowing, and I am convinced that once the leech reaches the stomach it is killed. I have never heard of any after symptoms from cases where to my knowledge a leech has been completely swallowed. Many patients can describe the actual moment (during deglutition) when the leech seizes on the throat. One would suppose from the great frequency of leeches in the mouths of horses, etc., that they must sometimes find a temporary resting place there in the human subject; such cases do not however come into the hands of a medical man—the patient or his friends readily removes such an intruder. In the cases, some three dozen or so, which I have had under my own observation the leech has been attached to the epiglottis, the pharynx, the nasal cavities, or—most common of all—the larynx. The frequency of the last situation in my clinical experience is doubtless due to the inability of the fellahin to do anything themselves for the relief of such cases.