OF THE SOUTHERN APTERYX. 265 
The lining membrane of the pharyna, behind the glottis, forms two elongate, square- 
shaped, smooth, thick, and apparently glandular folds or processes, the obtuse free 
margins of which project backwards, like lappels, into the pharynx’; beyond which 
the lining membrane is produced into close-set, narrow, somewhat wavy, longitudinal 
folds. 
The ewsophagus is continued down the right side of the neck, behind and a little to 
the right of the trachea, through the thorax and diaphragm to the proventriculus, with- 
out forming any partial dilatation or crop. 
The upper extremity of the wsophagus is rather wider than the rest of the tube, mea- 
suring from half an inch to an inch in diameter, according to its state of contraction : 
it gradually diminishes to a diameter which I found in one specimen to be 3, in another 
6 lines, and continues, without variation of size, to the proventriculus. The wsophagus 
is connected somewhat closely to the trachea, and by a looser cellular tissue to the 
surrounding parts. The muscular coat of the esophagus is about half a line in thick- 
ness ; its external fibres-are arranged circularly ; its internal ones form a longitudinal 
stratum. The ultimate muscular fibres are smooth, slightly wavy, and reticularly 
intermixed, but with a definite course. The internal membrane in the contracted e@so- 
phagus is disposed in narrow and slightly wavy longitudinal rugz, which become more 
close-set and strongly marked at the lower part of the canal: when viewed with a mag- 
nifying power the whole internal surface presents a delicate reticular structure. The 
length of the gullet is 9 inches. 
The proventriculus* is a narrow elongated cylindrical cavity in the azis of the eso- 
phagus, of which it is an immediate continuation. In one specimen it measured 1 inch 
2 lines in length and half an inch in diameter, in another it was 14 inch in length and 
linch wide. The gastric glands are developed around its whole circumference, and are 
closely packed together ; they are narrow elongated follicles, from 14 to 2 lines long, 
mostly bilobed, but sometimes more subdivided at their cecal or outer extremities*. The 
glandular parietes of each follicle consists of minute tubuli placed at nearly right angles 
with the central cavity. The muscular coat covering the glands is somewhat thicker 
than in the membranous part of the gullet, which is chiefly caused by the increase of 
the outer circular stratum of fibres, by the action of which the secretion of the glands is 
squeezed out into the cavity of the proventriculus. The longitudinal ruge of the lining 
membrane gradually subside at the entry of the proventriculus, where they run into each 
other, and so form a general reticulate surface, in the meshes of which the orifices of 
the gastric glands are situated. 
The epithelium lining the glandular part of the stomach is gradually condensed to- 
wards its lower part into a cuticle, which, as it passes into the muscular compartment, 
assumes a brown colour and a callous hardness, and forms a stratum about one-third 
of a line in thickness. In the Cassowary and Emeu the proventriculus is marked off 
} Pl. XLVIII. e. Fig. 1. 2 Pl. L. & LI. a. > PL LI. fig. 2 & 3. 
VOL. II.— PART Iv. 2N 
