THE ORIGIN AND DEVELOPMENT OF GASTRIC GLANDS. 75 



4, 5, 6 and 7 of a larval Desmognathus 13 mm. long. The gland 

 fundament here extends laterally throughout at least four sec- 

 tions (40 micra), or, perhaps, six as it is extremely difficult to 

 trace out all the individual cells of such a series. As yet there is 

 no lumen apparent in the gland (Figs. 1-7). A section through 

 the center of the gland is shown in Fig. 6. This shows the in- 

 sinking (d} at the surface, and the arrangement of the nuclei of 

 the surface epithelium around the gland as an axis (). Fig. 4, 



FIG. 9. Same as Fig. 8. ._ the cells of the gland fundament are arranging 

 themselves about the gland lumen in a way to indicate the approaching union of the 

 duct and fundus at n. (the neck cells) ; <>/., the epithelial cells show the lateral 

 displacement, which gives rise to the duct, to a marked extent. 



a section nearer the edge of the gland, shows the arrangement of 

 the nuclei of the cells around one end of the gland (a). This same 

 series (Figs. 4-7) also shows another interesting fact, which in- 

 deed holds true for all the animals studied. While the stomach 

 is being differentiated from the entoderm all the above processes 

 are taking place at the same time, so that in the same series are 

 found gland fundaments in different stages of development. So, 



