The Digestive System 167 



the epithelium is greatly increased, and at the 

 same time the horny la\^er is also thickened, to form 

 distinct papillae like the one shown in the figure. 

 These, as has been said, are comparatively small 

 and have the shape of a blunt cone. The center of 

 the cone is, of course, made up of the cellular 

 epithelium, while the outside is covered with the 

 thickened horny layer from which fibers, /, are 

 often seen projecting. Near the apex of the cone 

 the nuclei are larger and more widely scattered 

 than those at the base. 



No glands were seen in the roof of the mouth 

 of the hibernating animal, but since the entire roof 

 was not sectioned it is probable that they may 

 exist in some regions; in fact, as noted below, sec- 

 tions through the posterior region of the roof of 

 the mouth of the feeding animal do show numerous 

 glands. 



As might be expected there is comparatively 

 little difference between this region of the enteron 

 during hibernation and during the feeding season. 

 The only noticeable difference is in the stratified 

 epithelium ; that of the feeding animal not only has 

 less sharp papillae but has also a much thinner scaly 

 layer of cells. As is seen in the figure of the roof 

 of the mouth during hibernation the scaly cells 

 make up, except on the papillse, nearly or quite 

 half of the thickness of the epithelium, while in the 

 feeding animal they make up not more than one 

 fourth or one third of the entire epithelium. Very 



