Formation of polar bodies in Asterias glacialis. (Slightly modified from Hertwig.) In I the polar spindle (sp) has advanced to the surface of the egg. In II a small elevation (pb1) is formed which receives half of the spindle. In III the elevation is constricted off, forming the first polar body (pb1), and a second spindle is formed. In IV is seen a second elevation which in V has been constricted off as the second polar body (pb2). Out of the remainder of the spindle (f.pn in VI) the female pronucleus is developed.
Plate
InfoField
4
Date
before 1858
date QS:P,+1858-00-00T00:00:00Z/7,P1326,+1858-00-00T00:00:00Z/9
Source
Henry Gray (1918) Anatomy of the Human Body (See "Book" section below)
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{{Information| |Description= {{Gray's Anatomy plate|Formation of polar bodies in Asterias glacialis. (Slightly modified from Hertwig.) In I the polar spindle (sp) has advanced to the surface of the egg. In II a small elevation (pb1) is formed which recei