The Structure of the Mammalian (sophagus. 17 
border of the epithelium presents a somewhat irregular outline in 
section. 
The lamina muscularis mucose is well developed, except at the 
very beginning of the cesophagus. It forms a continuous layer com- 
posed of two or three layers of longitudinally disposed bundles of 
unstriated muscle. 
The glands of the lower pharynx are mixed glands containing 
mucous portions with demilunes and serous alveoli. 
The external muscular coat is composed of striated muscle through- 
out the whole length of the cesophagus. 
CHIROPTERA. 
This order is represented in my material by a single alcoholic 
specimen of Vespertilio fuseus, the brown bat. 
The epithelium in the csophagus of Vespertilio is thin (30-45 
micra), and shows no stratum corneum, although the cells of the 
superficial two-thirds of the epithelium are much flattened. No 
papille are present. 
The muscularis mucose is exceptionally well developed, reaching 
a thickness of 50 micra in the lower third of the cesophagus. It 
forms a continuous layer and consists of smooth muscle arranged 
longitudinally. 
No glands are found at any level in the cesophagus. 
The external muscular coat consists of striated muscle in the upper 
two-thirds and unstriated in the lower third. 
CARNIVORA. 
In the Carnivora the esophagi of the following species, hitherto 
undescribed, have been examined: Proeyon lotor, Lutreola vison, 
and Mephitis mephitica. One cesophagus of each species was avail- 
able for this study including in the case of Procyon and Mephitis 
the whole of the cesophagus and the adjacent portions of the pharynx 
and stomach, in Lutreola the cesophagus and stomach only, so that in 
the latter animal the pharynx and transition region was not obtained. 
In addition the csophagi of the cat and dog were examined to con- 
firm the work of earler observers. In these animals preparations 
