Figure 6H represents a section through the plane 820 of figure 6A. The section is caudad to one lung and cuts the extreme tip of the other, _lu_. The liver, _li_, and pancreas, _pan_, are seen at the side of the stomach, _i'_, here cut through its greatest transverse diameter. The epithelium of the stomach varies somewhat in thickness and consists of two or three layers of cells, the variation in thickness being due to a variation in the length of the cells rather than to a variation in the number of layers. Ventrad to the stomach the intestine, _i_, is cut in three places, of which the most dorsal section is the largest. The epithelium of these intestinal sections, especially the lower two, consists of usually a single layer of columnar cells which are clearer than those of the stomach. A fairly thin mesentery, _ms_, supports this region of the intestine. In the region of the posterior appendages, _pa_, the section passes through the hindgut, _hg_, and allantois, _al_. The former is of about the same size as the more anterior sections of the intestine, but its epithelium is less clear and is composed of two or more layers of cells. The allantois is cut near its opening into the hindgut; its walls are thin, the epithelium consisting of but a single layer of more or less flattened cells. Figure 7 represents a reconstruction of the enteron of an embryo of 42 mm. crown-rump length. Because of the body flexure and large size of the embryo the head was amputated, in the plane _a-b_, and cut sagitally, while the body was cut transversely in the direction shown by the section planes. In the present figure the outline of the embryo, including the eye, appendages, and umbilical stalk, is shown by fine dotted lines; the outlines of the lungs and liver are shown by heavier, broken lines; while the outlines of the enteron proper and the trachea are shown in solid lines, filled in which fine stippling. For the sake of simplicity only one lung and one bronchus are shown. Since the head has now quite a reptilian form, the oral cavity, _m_, has more or less of the adult outline. A transverse groove near the anterior end of the lower jaw marks off the tongue, _tn_; and the rudiments of teeth are seen but not shown in the figure because of the low magnification used. The pharynx, _ph_, is a very extensive cavity that is sharply separated from the mouth by a prominent transverse fold of skin, the velum palitum, _vp_, just in front of the posterior nares, _pn_, and by a less marked fold from the base of the tongue; it is these two valves that enable the adult alligator to open its mouth under the surface without getting water into the lungs. The mouth and pharynx are lined at this stage with a thin, stratified epithelium, which consists of a basal layer of rather tall columnar cells and one or two superficial layers of flattened cells. The pharyngeal epithelium is rather thicker than that of the oral cavity.