when the tongue is densely furred, they stand out as bright red spots. The back of the tongue is crossed by a =V=-shaped row of papillæ of larger size, each surrounded by a slight fossa and a vallum, and hence termed “circumvallate.” Very minute organs of sense—taste-bulbs—stud the mucous membrane which lines the fosse. The hard palate ends in a muscular curtain—the soft palate—the central portion of which—the uvula—depends lower than the rest. On either side the soft palate splits into two folds; the anterior, continued to the side of the tongue; the posterior, to the pharynx. These folds, since they bound the gateway into the pharynx, which is known as the “fauces,” are termed the “pillars of the fauces.” The tonsil lies between the anterior and posterior pillars of the fauces, but does not appear as a prominence unless inflamed or enlarged. The pharynx hangs as a bag from the base of the skull. It, like all the rest of the alimentary tract, is lined by mucous membrane. “Mucous membrane” is not a happy term. It does not denote that the epithelium secretes mucus. It may or may not possess this property. Nor does it imply that it has a different origin from the skin—that it arises from hypoblast, the inner layer of the rudiment from which the embryo grows. The term is applied to all internal, and therefore moist, surfaces, whether they arise from hypoblast, as in the case of the lining of the greater part of the alimentary tract, or whether they are involutions of epiblast as in the case of the mouth and also of the extreme lower end of the alimentary tract. Almost the whole of the alimentary canal is, in the first instance, a tubular cavity in the interior of the embryo, lined by hypoblast. This cavity communicates with the yolk-sac, but has no openings on the exterior until it joins up with two epiblastic pits—one the stomodæum, or mouth-cavity, at the anterior end; and the other the proctodæum, at the posterior end of the body. The distinction between the middle closed portion of the alimentary canal and its two secondary openings suggests morphological speculations, into which we have not space to enter, as to the ancestry of the vertebrates. The majority of anatomists believe that the primitive canal is represented in the middle portion, and that, in prevertebrate animals, it opened to the exterior in a different way. The pharynx is 4½ inches long. It is enclosed by three thin muscles, which overlap from below upwards—the constrictors of the pharynx. The anterior attachment of the superior constrictor is to the jaw; of the middle constrictor to the hyoid bone; of the inferior constrictor to the thyroid cartilage. Above the soft palate the nasal chambers communicate with the pharynx by the posterior nares. Below the hyoid bone, which is easily felt in the neck as a bony arch just above the thyroid cartilage (Adam’s apple), the windpipe, or trachea, joins the pharynx by a single pear-shaped orifice—the rima glottidis. When we