The Structure of the Mammalian Csophagus. 13 
My observations are in accord with those of Ranvier (84), Briim- 
mer (76) and others who deny the presence of cesophageal glands in 
rodents. In none of the species mentioned above are cesophageal 
glands to be found below the level of the cricoid cartilage. In the 
rabbit, pocket gopher (Geomys) and chipmunk (Tamias) groups of 
mucous glands were found above this layer in the submucosa of 
Stratum 
corneum 
SS —— Stratum 
granulosum 
—— Stratum 
germinativum 
Lamina 
propria mucose 
——/. muscularis 
MuUucOse 
Tunica mucosa of cesophagus of guinea pig. Showing true stratum cor- 
neum and stratum granulosum. > 120. 
the pharynx, and it is probable that the occurrence of glands in this 
portion of the pharynx is responsible for the statements of Graff 
and of Vogt and of Yung that glands occur in the esophagus of the 
rabbit. 
The cesophageal epithelium in the rodents is a thick layer of strati- 
fied squamous cells presenting in the different members of the order 
two main types. One type (Fig. 5 A) is characterized by a very rapid 
