The American journal of anatomy . a O 0„ ° o o O c. Fig. 2 ones appear in the middle zone. Likewise, the smallest granulesdo not appear in the lower zone. Contrary to Jordan (93), Houssay (90) and others who main-tain that the size of the yolk granules are of no value for deter-mining the future history of the various regions of the egg, I havefound that until after gastrulation at any rate, the differencesin size of the yolk granules afford a highly efficient means for 178 HUBERT DANA GOODALE determining the distribution of the egg material. The yolkgranules undergo little change during the e
The American journal of anatomy . a O 0„ ° o o O c. Fig. 2 ones appear in the middle zone. Likewise, the smallest granulesdo not appear in the lower zone. Contrary to Jordan (93), Houssay (90) and others who main-tain that the size of the yolk granules are of no value for deter-mining the future history of the various regions of the egg, I havefound that until after gastrulation at any rate, the differencesin size of the yolk granules afford a highly efficient means for 178 HUBERT DANA GOODALE determining the distribution of the egg material. The yolkgranules undergo little change during the early part of develop-ment. A brief account of the later history of the granules is givenhere in order to afford a connected account of the distributionof egg materials into some of the embryonic organs. In fig. 14,a vertical section of an eight-celled stage, the general distributionof yolk granules has been represented; / indicates the regionoccupied mostly by fine granules, i the region of intermediategranules and y the region of large granules.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectanatomy, bookyear1901
