The roof of the mouth is anteriorly a little concave, with a median prominent line; the palate convex; the lower jaw with a kind of joint about an inch from the base, its intercrural membrane or skin very extensile. The tongue is 1-7/12 inch long, very slender, trigonal, emarginate at the base, with a groove along the middle, and pointed. Posterior apertures of nares linear, 1/2 inch long. Œsophagus, _a_, _b c_, 10 inches long, its walls delicate, its diameter at the upper part 1-1/4 inch, gradually contracting to 1/2 inch at its entrance into the thorax. The lobes of the liver unequal, the right 1 inch 5 twelfths long, the left 11 twelfths; the gall-bladder large, 7 twelfths long. The stomach, _c_, _d_, is membranous, of an oblong form, 9 twelfths long, 10 twelfths in breadth; its tendons elliptical, twelfths by 3 twelfths. The proventriculus, _c c_, 9 twelfths long, with a complete belt of oblong glandules. There is a small roundish pyloric lobe _e_. Intestine, _f_, _g_, 2 feet 11 inches long, its diameter uniform, 1 twelfth, or about the thickness of a crow’s quill. Rectum enlarged to 3 twelfths, and 3-1/4 inches long, its cœcal extremity rounded, and only one-twelfth long. The trachea is 7-1/4 inches long, of nearly uniform diameter, averaging 2 twelfths; the rings 160, nearly circular and ossified. The bronchial half-rings about 18. The lateral muscles are very inconspicuous; sterno-tracheals; and a pair of inferior laryngeal, going to the first bronchial rings. [Illustration] The Herons generally differ from the other Grallæ in having the œsophagus much wider and similar to that of the fish-eating palmipedes; the stomach in a manner membranous, like that of the rapacious land-birds, without lateral muscles or strung epithelium; the intestine extremely slender, and the anterior extremity of the large intestine or rectum furnished with a single cœcum, in place of two, as in almost all other birds. BLACK-BELLIED PLOVER. _CHARADRIUS HELVETICUS_, WILSON. PLATE CCCXXXIV. MALE IN SUMMER, YOUNG, AND ADULT IN WINTER.