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EXPLANATION OF FIGURES 
Plate XXIX 
All the figures of this plate are from the chromosomes of Tradescantia virginica L. 
Figures 1, 2, 3, 4, 5, 7, 8, and 12 are freehand. Figures 6, 9, 10, 11, and 13 are drawn 
with the camera lucida at table height (1600 diameters), with 2 mm. Zeiss apochromatic 
objective N.A. 1.4 with iox compensation ocular, at 160 mm. tube-length and with critical 
illumination. 
Fig. 1. Portion of a metaphase chromosome teased from a partially injured cell into 
the suspension fluid. 
Fig. 2. Portion of a metaphase chromosome from the same cell. 
Fig. 3. Enlarged end views of two separate chromosomes from different cells. 
Fig. 4. Enlarged end view of another chromosome. 
Fig. 5. Chromosome a, figure 6. The numbers are given for convenience in refer¬ 
ring to individual chromomeres. 
Fig. 6. Chromosomes of a pollen mother cell in the homoeotypic division. The lower 
dotted line represents the outline of the nucleus belonging to the other sister spindle which 
completed its dispireme in advance of the one drawn. 
Fig. 7. A chromosome of the equatorial plate, first division, teased from the same 
cell as were those of figures 1 and 2. It was slightly damaged in the process, and I ascribe 
the constriction to the teasing. The upper figure shows the appearance at the top focus; 
the lower one is from the deeper focus. 
Fig. 8. Chromosomes of the equatorial plate, first division, showing subdivision of 
the chromomeres. Taken from a perfect cell and a common figure. 
Fig. 9. Metaphase chromosomes of the first division. 
Fig. 10. Metaphase chromosomes with marked nodular outlines. 
Fig. 11. Late prophase or diakinesis just prior to the equatorial plate stage. 
