The Structure of the Mammalian (sophagus. 31 
suitably fixed material. In one out of four wsophagi of which total 
preparations were made to study the distribution of the glands, groups 
of these glands were found in the upper part of the cesophagus 
extending 4.5 em. below the lower border of the cricoid cartilage. 
In this case twelve patches of these glands were found varying in 
size from 1 mm. to 15 mm. in length and from 1 mm. to 3 mm. in 
width. 
The mucous tubules and acini are surrounded by a well marked 
basement membrane composed of reticulum, and the tubules are bound 
together by a reticular framework. No myoepithelial cells could be 
demonstrated between the basement membrane and the epithelium 
of the glandular tubules. 
The epithelium in man is of considerable thickness, varying in 
this respect with age, and with the degree of tension of the mucous 
membrane. Another cause of variation in thickness in specimens 
of the human csophagus is due to post-mortem loss of the super- 
ficial layers of cells owing to maceration. In the newborn child it 
has a thickness of 113 micra, in the adult from 260 to 440 micra. 
The degree of cornification of the epithelium in man is about the 
same as in the pig and considerably less than in the sheep and ox, that 
is to to say that, although the superficial layers of cells show indica- 
tions of chemical change in their greater transparency and in stain- 
ing more readily in eosin, the degree of flattening of the cells is much 
less than in the animals mentioned, and oval nuclei, which stain 
well, are preserved even in the most superficial layers (Fig. 13). 
The deep border of the epithelium is irregular owing to the pres- 
ence of transitory folds of the lamina propria, described by Strahl 
(89) and more particularly owing to the presence of large numbers 
of high conical papille. The latter are arranged in linear rows 
running parallel to the axis of the cesophagus and resembling in 
their general arrangement those found in the skin of the palmar sur- 
faces (Fig. 17). In some cases; as shown in the figure, the rows are 
composed of several ranks of papille, the individual papille being 
irregularly distributed. 
The lamina muscularis mucose is well developed. It begins in 
the lower part of the pharynx as scattered bundles of longitudinally 
