528 Franklin P. Johnson. 
through an angle of about 90 degrees and always in the direction 
of the hands of a clock, seems to have some significance. Just 
what the cause of this rotation may be is debatable. Kreuter 
discards the idea that the lower part of the cesophagus may share 
in the rotation of the stomach. However, this may be its cause. 
This view is supported by the arrangement of the branches of 
the vagus nerves. These branches are also twisted at the same 
level as the cesophageal folds. It would, therefore, not seem 
improbable that the lower part of the oesophagus had been 
twisted along with the nerves by the stomach. Since the twisting 
of the stomach takes place before the appearance of the folds, it 
would necessarily have to be assumed that the lines along which 
the first eesophageal folds develop are marked out before the actual 
appearance of the folds themselves. 
Ciliated cells. The presence of ciliated cells in the cesophagus 
was noted in 1876 by Neumann, who observed them in em- 
bryos of from 18 to 32 weeks. He described the epithelium 
as stratified, the superficial layer being made up of patches of 
both ciliated columnar and squamous cells. Schaffer (04), con- 
firmed by Jahrmaerker (’06) and Schridde (07), states that the 
ciliated cells may extend through the thickness of the epithelium 
down to the basement membrane. Jahrmaerker has recorded the 
presence of ciliated cells in the cesophagus of an embryo at 44 
mm. In an embryo of 42 mm. no ciliated cells could be found, 
but the preservation of this embryo was poor and the staining 
unfavorable for the recognition of cilia. In a specimen of 55 mm. 
ciliated cells are abundant. Here the epithelium of the cesophagus 
is composed of from two to four layers of cells with distinct cell 
boundaries. The basal cells are columnar and have their oval 
nuclei away from the basement membrane. In those places where 
there are not more than two layers of cells, the superficial cells 
are columnar, very granular, and ciliated. Where there are three 
_or four layers of cells, only the lower layer is columnar, the upper 
layers being composed of polygonal or flat cells. 
In order to study the distribution and number of the ciliated 
cells, wax reconstructions were made, the areas of ciliated cells 
being carefully painted on each wax section before piling. Fig. 
