Page 191. 
320 ON THE ANATOMY OF CHAUNA- DERBIANA. 
obtusely triangular, with a small papillary fringe at its extremity, 
% of an inch broad. The base is straight, and is edged with spines 
zs of an inch long, and shorter, directed backwards. The surface 
and lateral margins are quite smooth, the whole organ being flattened, 
slightly grooved longitudinally down the centre, and nowhere more 
than $ of an inch thick. At its base are two lateral juxtaposed 
protuberances, rough on the surface, and together equal in area to . 
one-third of its surface. There is no transverse constriction or 
oblique groove like that found on the surface of the tongue in some 
Anatide. 
The esophagus is uniform in diameter, no crop being even indi- 
cated ; it is not capacious. 
The proventriculus is peculiar. It is more than usually capacious, 
and is glandular only in a patch which occupies but a small portion 
of its surface. This patch (which is clearly shown in the represen- 
tation of this portion of the alimentary canal in Plate [14] XII. fig. 1, 
at its upper end, where the proventricular dilatation ceases) has a 
narrow zonary belt of glands. It can, however, be seen that by 
far the majority of the glands are aggregated into a posteriorly 
situated patch. The only birds with which I am acquainted in 
which the proventricular glands do not form a zone, or an approach 
to one, are Struthio and Rhea. In the Galline and Anseres they form 
a zone. 
The glandular surface occupies a subelliptical space, 2 inches by 
13 in its long and short diameters, in the upper and back part of the 
canal, with the long axis in the direction of the tube. Its lower end 
is 22 inches from the upper orifice of the gizzard. ‘The gland-tubes 
are simple, not racemose, and average } inch in length. The remainder 
of the area of the proventriculus, above five-sixths of it, is covered 
with coarse and irregularly folded epithelium. 
The gizzard is constructed on the usual type; it is decidedly small 
in proportion, to the size of the bird (in the Anseres it is as con- 
spicuously large), being much more elongate, narrow, and less muscular 
than in grain-feeders. Longitudinal folds plicate the triturating 
surfaces, which are smooth in the Geese, Ducks, and Swans. 
The spleen is the size of a haricot bean, and of much the same 
shape. Its position is in no way peculiar; but, as in all birds, being 
placed above the gizzard, it tends to confirm the opinion that the latter 
organ is only the representative of the pyloric end of the stomach, 
the cardiac component of which is represented by the proventri- 
culus, 
The liver is composed of two simple rounded lobes, united by a 
narrow isthmus of hepatic tissue; the lobes are of nearly equal size; 
and there is a fairly voluminous gall-bladder. 
