90 MARY J. ROSS. 



(Figs. 30, 31, 32,/, it}. The duct cells are a little rounder and 

 more granular than the rest of the stomach epithelium, hence 

 they might more properly be termed neck cells (Figs. 27, 28, 32, 

 d} as they correspond to the neck cells found in Desmognathus 



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 l...<-r- 



FIG. 29 represents a section from the fundus of the same stomach as in Fig. 28. 

 These two figures are taken from an earlier stage than Figs. 30 and 31, before the 

 primary processes have begun to develop. 



(Fig. 14, 11). In this case the greater part of the future excretory 

 duct still lies on the surface as surface epithelium. This is prob- 

 ably the true explanation, for the cells around the lumen of the 

 glandular pits multiply and project out in all directions into the 

 cavity of the stomach, forming secondary ridges. These secon- 

 dary growths (Fig. 32, s/} appear on the sides and crests of the 



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FIG. 30. .Section through the pyloric region. Here is shown the same condition 

 as in Fig. 32. Letters as in Fig. 28. Formalin. Obj. T L, Oc. 2. 



ridges already formed and in the depressions or hollows between 

 them. The connective tissue also takes part in the formation of 

 these secondary processes, projecting upwards as a central core, 

 as shown in Fig. 32, c. At first these projections do little more 

 than deepen the shallow pits, before described. As development 

 proceeds further these processes become approximated (Fig. 32, 



