Entity of the Karyokinetic Spindle in Mitosis of Sea Urchin Eggs

Abstract

1. Applying improved cytological techniques, the nuclear origin of the karyokinetic spindle and the presence of the spindle membrane are demonstrated in the mitosis of sea urchin eggs.2. The biological significance of the spindle membrane is discussed free from any preconcieved ideas as described in current cytology text-books.