PLATE 1 
EXPLANATION OF FIGURES 
The figures are all taken from the gastric epithelium of embryos fixed in a 
mixture of 10 per cent formalin and 2 per cent chromic acid. 
2 The earliest recognizable stage in gland development of an embryo 133 
mm. long. Iron haematoxylin-orange G stain. > 1000. 
3 The formation of definite gland rudiments in the epithelium of a specimen 
137 mm. in length. Iron haematoxylin-orange G stain. »X 1000. 
4 QOutgrowth of a gland rudiment and extension into the underlying meso- 
dermie tissue in an embryo 137 mm. long. Iron haematoxylin-orange G stain. 
x 1000. 
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