Overton—On the Boot Tips of Podophyllum Peltatum. 315 
down between adjacent chromosomes by the interosculation of 
neighboring vacuoles. 
13. The anaphasic and telophasic vacuolation of the chromo¬ 
somes has no direct relation to the longitudinal splitting of the 
chromosomes, this splitting being entirely prophasic. 
14. Evidence exists that the chromosomes are individualized 
structures persisting as such in different forms throughout all 
stages of division and rest. 
15. The heterotypic division separates whole chromosomes 
which have previously been laterally paired (see Overton, ’05). 
16. No evidence was found to support either Merriman’s or 
Bonnevie’s theory of chromosome structure. 
17. The results do not support the interpretation of Fraser and 
Snell, Lundegard, Digby, and others as to the duality of nuclear 
structures. 
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