PHOTOdRM'IIY 



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Fig. 22.^ — Photograph of twelve chromosomes united in a chain or ring in Rhoco 

 discolor. Stained and fixed in iron-acetocarmine. Pollen mother cells squeezed 

 from the cell walls. Taken with apochromatic water-immersion objective 70, and 

 Siedentopf's photographic attachment. Enlarged on positive lantern slide, from 

 which a negative was made. 



Fig. 23." — Photograph of first-anaphase chromosomes in a pollen mother 

 cell of Lilium pardalinum. Smear fixed with chrom-acetic-formalin, and stained 

 with iron-hrazilin. Mounted in cedar immersion oil. Pressed flat. Taken 

 with apochromatic objective 90 of IM aperture. Other details as in Fig. 22. 

 This figure shows the zigzag (not spiral) bends of the anaphase chromosomes, 

 seen only in well-fixed i>reparatioiis. 



