136 



CHAS. B. WILSON. 



original form, thereby carrying the polar bodies nearer the 

 membranes. 



In one or two instances the recovery was carried so far 

 that the polar bodies were pushed out into the membranes 

 as in fig. 39. 



This figure shows that there are two independent mem- 

 branes, for only the inner one is bulged outward to any 

 extent. 



It also shows that the first polar body is surrounded by a 

 zone within which spinning activities are sufficiently strong 

 to prevent the membrane from entering. The relative 

 distance of the two bodies from each other and from the egg 

 does not seem affected at all by this contact with the mem- 

 brane, so that the latter must be very delicate and yield 

 readily to slight pressure. The second body in pinching olf 

 from the egg also leaves a narrow band of connecting proto- 

 plasm (fig. 35), which keeps both bodies in close relation 

 to the egg. 



When separated it begins to show activities somewhat 

 different from those of the first body (fig. 36). While 

 forming, fine threads are seen radiating outward from 

 nearly all visible parts of its surface, but as soon as it 

 assumes its characteristic spindle shape the two poles at the 

 extremities of the spindle become the centres of filose 

 activity. 



At first they send out slender threads in various directions, 

 but soon they begin to elongate as pseudopodia processes (fig. 

 35), carrying the centre of activity away from the body itself. 

 The ends of the processes enlarge, and may even form secon- 

 dary spindles, from which fine threads radiate in all direc- 

 tions (fig. 38). Short filaments still appear and disappear at 

 different points on the body itself, but they are very transi- 

 tory, and evidently of secondary importance. 



In unripe eggs, and especially in those developed under 

 abnormal conditions, the spinning activities may be greatly 

 increased. These are the eggs usually covered with papillae 

 in the vicinity of the polar bodies, and the abnormal spin- 



