English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Our intention in carrying out the experiments described in the following pages was to determine: 1) whether the eggs of the sea urchin, rotated at a high rate of a speed on a centrifugal machine, become orientated as they fall so that the original polar axis coincides with the new axis, or whether any diameter of the egg may become the axis of stratification; 2) whether the embryonic axes conform to the axis of the induced stratification; 3) whether the materials separated by the centrifugal force into zones are formative materials; and 4) whether a readjustment of the contents takes place before or after the cleavage, for, while a study of the surface views shows that the pigment retains very largely the configuration induced by the rotation, it is possible that the contents of the egg might return to their original arrangement. It became necessary to section the eggs to settle this question.

The relation of the substances of the egg, separated by a strong centrifugal force, to the location of the embryo