252 H. M. KINGERY. 



EXPLANATION OF PLATES. 



All the figures are camera-lucida drawings made from the actual preparations. 

 All the drawings except Figs. 3, 7, and 14, were made by Miss Cora J. Whitman. 



PLATE I. 



FIG. i. Primary oocyte, containing a first polar spindle. The chromosomes are 

 longer and more slender than usual in first polar spindles. The zona pelludica is 

 seen surrounding the egg-cell (zp.). X 670. 



FIG. 2. Primary oocyte containing a first polar spindle, of the "barrel-shaped" 

 type. The chromosomes are of the type usual for this spindle. The zona pellu- 

 cida has disappeared. X 670. 



FIG. 3. Secondary oocyte, with second polar spindle and polar body which 

 also contains a spindle more or less deranged. Some of the chromosomes of the 

 egg spindle have been omitted from the drawing in order to show more clearly the 

 characteristic shape of the chromosomes of the second polar spindle. X 670. 



FIG. 4. Secondary oocyte, with second polar spindle and polar body. Cen- 

 trosomes are seen at each end of the spindle. X 916. 



