356 



W. J. C. Laweence 



Cytologia 2, 



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Fig. 1. 



Fig. 1. Meiosis in Dahlia Merckii. (2n=36) 



a. mid-diakinesis. 6. late diakenesis (bivalents at top focus shown in black, mid- 

 dle focus stippled, bottom focus in outline), c. pro-metaphase. d. side-view MI 

 (incomplete) showing secondary association of bivalents. e. association of 3 bivalents 

 of similar configuration, f-j. polar views MI, showing association of bivalents in 

 twos and threes. y= maximum association (2 groups of 3 bivalents & 6 groups of 2 

 bivalents). 



Me iap/iase 



An outstanding feature of the distribution of the chromosomes at 

 this stage is the association or approximation of separate bivalents 

 (Figs. If-i). This association varies considerably, ranging from actual 

 contact, perhaps an artifact, to a point where it ceases to be apparent. 

 The degree of association in a given group may sometimes vary among 



