On the Histogenesis of Gastric Glands. 513 
be mentioned. The neutral gentian stain was used on every stage 
of cardiac development. This was done purely as a matter of 
routine, as I never anticipated finding anything in the cardiac 
tubules staining specifically with it, except the copper red granules 
of the parietals. But at 25 cm. and thereabouts granules resem- 
bling zymogenic granules appear in the deeper cells of undoubted 
cardiac tubules. Adjacent sections stained with muchematin 
show these same cells tobe mucous chief cellsof the ordinary type, 
so that the granules lie within the mucous parts of the cell. These 
granules are found intracellularly for one or two (em.) stages, 
and after that disappear. I did not find them in the extreme left 
cardiac region. 
At birth, the cytodifferentiation of the cardia is incomplete, or, 
rather, that involution required to bring about the adult cyto- 
logic status, with its single type of gland cell, has not yet begun.! 
Caecum. At 10 cm. the glands are rather sparsely distributed. 
Many are as deep as the pyloric tubules, but contain few or many 
parietals. By 15 cm. the glands are almost as thickly distributed 
as in cardia or fundus, the parietals are abundant, and the tubules 
have the general characters of those of cardia and fundus, ap- 
proaching more the deeper form of the fundic tubules. In later 
stages this region undergoes the same change as the general 
cardia. 
5. Pars oesophagea 
The greater part of this region gradually becomes stratified 
during the 6 to 10 cm. stages, the cells still remaining clear and 
transparent, except those of the deepest layer, which have acquired 
a finely granular cytoplasm of the ordinary type. The clear cells 
of the superficial strata have already begun to flatten out. At 
the periphery of the stratified area, the columnar cells constituting 
the deepest layer, are continuous with the simple columnar epi- 
thelium of the surrounding zone. We have seen that at 4-6 cm. 
a narrow, peripheral zone of this region has developed gland 
8 Negrini, 1886, noted that parietals are present in the foetal, but absent in 
the adult cardia; also Bensley, 1903. 
