PLATE 3 
EXPLANATION OF FIGURES 
14A and B No long Toxopneustes rod. Some of both Toxopneustes and 
Arbacia chromosomes have been eliminated. 
15A and B- No Toxopneustes Vs. Some of the Arbacia chromosomes seem 
to be absent. 5 
16A, Band C NoToxopneustes Vs. Some of both Toxopneustes and Arbacia 
chromosomes have been eliminated. 
17A, Band C Pronounced lagging of Toxopneustes chromosomes. 
Toxopneustes 9 XX Arbacia o cross 
18A, B and C Lateral view of anaphase plates. Two Toxopneustes Vs and 
the long rod. Few Arbacia chromosomes. 
19A and B_ Lateral view of anaphase plates. Two Toxopneustes Vs and the 
long rod. Few Arbacia chromosomes. 
20A and B. Nearly all of the Arbacia chromosomes are absent. 
21A and B Tripolar figure. Two pairs of Toxopneustes Vs are present. 
Probably about half of the Arbacia chromosomes have been rejected. 
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