PLATE 12 



EXPLANATION OF FIGURES 



6-ito69 Stenotomus chri/sops 9 X Ctenolabrus odsperaus d'. 



64 Metaphase of second cleavage. Chromatin is being pushed out by the 

 lengthening astral fibers toward the first cleavage plane. 



65 Prophase of the second cleavage. The chromosomes extending toward the 

 first cleavage plane were probably left there during the first cleavage. 



66 A section through a two-celled egg in the metaphase of the second cleavage. 

 The section passes through the equatorial region of both spindles, which are 

 connected by fibers. Chromatin occurs along the course of the connecting fibers. 

 Magnification is approximately 810 diameters. 



67 Anaphase of the second cleavage in two sections, A and D. A is supple- 

 mented by extra drawings, B and C. B shows the elements from section a which 

 appear in one plane. C shows on a larger scale the form of the comi)ound chro- 

 mosome described in the text. 



68 Anaphase of the second cleavage in two sections, showing lagging chro- 

 matin. 



69 Telophase of the second cleavage showing lagging chromosomes. 



286 



