The Digestive System 159 



fixed in the usual fluids, the epithelial structures 

 from this animal were not as clearly defined in 

 most cases as could be desired; this rather 

 unsatisfactory fixation may have been due to 

 some physiological condition characteristic of 

 the period of hibernation. That this was the 

 case seems likely from the better fixation obtained 

 by the same methods in the case of animals killed 

 during the feeding season. 



The other animals from which tissues were taken 

 were considerably smaller than the one mentioned 

 above. They were killed early in the fall, after 

 having been fed regularly for about five months 

 upon bits of meat, both raw and cooked. 



The Tongue. The covering of the tongue was 

 studied in two regions, near the free end, and 

 towards the base. 



A section of the former region, drawn under high 

 power, is shown in Figure 36. It consists of a 

 dense mass of fibrous tissue, a, and small scattered 

 cells, overlaid by a stratified epithelium of eight 

 or ten layers. Only a small part of the fibrous 

 base, just beneath the epithelium, is here shown. 

 It is a dense areolar tissue with the elastic fibers 

 apparently predominating. 



The epithelium, e, consists, as has just been 

 said, of about eight or ten layers of cells, those at 

 the base being generally cuboidal in shape, while 

 towards the surface the cells become more and 

 more flattened until at the surface they form 



