86 MARY J. ROSS. 



composed of several layers. Sections cut at 2 micra show that 

 the epithelium is simple columnar; all the cells which reach the 

 surface also rest upon the basement membrane, the " pyramidal 

 cells" of Toldt ('80). In this respect the earlier stages in the 

 pig also resemble those found in DcsinognatJuis and Ainblystoma 



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V .-----.. '-'!. 5. /."/. .-;>'.: \ : "$ '?'.?*,-,- :~-.^ '.- , V - . ' 



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FIG. 23. Cross-section through the stomach of an Amblystoma of 16 mm. length. 

 The yolk has all been absorbed. This shows the gland in the adult condition. Sec- 

 tions of larvse of this size also show stages comparable to Figs. 13-18 of Desmogna- 

 thns. Fixed in Flemming's fluid, bin., basement membrane ; c. , connective tissue ; 

 ./., duct, which is very short in Amblystoma due to its late development ; <?/., epithe- 

 lial cells; /., fundus ; /., lumen; i., muscular layer ; ;;., neck of gland. Obj. J s , 

 Oc. 2. 



(Figs. 3, 19, 24). These round cells, appearing at the base of 

 the epithelium, rest upon the basement membrane (Fig. 24, ^). 

 They then divide, as described before for Desmognathus and 



