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180 stomach,—at least, nothing is said of any other part of the animal. I have never had an opportunity of dissecting the pulmonary system of a Boa, or of satisfying myself as to the structure of the extremely long trachea, which must be very firm to resist such an immense pressure; but I believe, from a near and accurate inspection, in company with others, that respiration goes on during the period of the greatest dilatation. While these Serpents are in the act of constringing or of swallowing their prey, they appear to be so entirely pervaded with the appetite which then governs them, that I am convinced they would suffer themselves to be cut in pieces before they would relinquish their victim. I have assisted in taking them up and removing them with their prey in their coils, without their appearing to be in the least disturbed by the motion, excepting that, if after the victim is no more, and the constriction is somewhat relaxed, an artificial motion be given to the dead body, they instantly renew the constriction. When thus employed they may be approached closely, and with perfect security, for the reason above stated; and I have uniformly found that the larynx is, during the operation of swallowing, protruded sometimes as much as a quarter of an inch beyond the edge of the dilated lower jaw. I have seen, in company with others, the valves of the glottis open and shut, and the dead rabbit's fur immediately before the aperture stirred apparently by the Serpent’s