PLATE 10 



EXPLANATION OF FIGURES 



52 to 54 Ctenolabrus adspersus 9 X Stenolomus chrysops d'. 



52 Typical anaphase figure of the fourth cleavage in two sections. Many 

 chromosomes omittted. 



53 Part of a section through a blastoderm killed four hovu-s and forty minutes 

 after fertilization. No lagging chromatin was noted in any of the dividing cells. 

 a, Black deposit which sometimes fills entire cells, usually peripheral cells. 

 (Drawn at table level with No. 2 ocular and Zeiss objective D). 



54 Polar view of an anaphase plate of the same stage as that from which 

 figure 53 was drawn. Forty-two chromosomes present. 



55 Stenotomtis chrysops 9 X Fmidulus heteroclitus cf. A mitotic figure from 

 an egg which had cleaved irregularly. Chromosomes of the Ctenolabrus type 

 are present. On the opposite side of the aster included in the figure are some 

 chromosomes which are not taking part in mitosis although they exhibit the 

 longitudinal cleft which precedes division. 



56 Stenotomus chrysops 9 X Fumlnlus heteroclitus cf . An early anaphase. 

 Only one section drawn. 



57 Stenotomus chrysops 9 X Ctenolabrus adspersus d' . A section through an 

 egg in the metaphase of the first cleavage. A — Cytoplasm. B — Yolk. Magni- 

 fication not recorded. 



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