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explanation of figures in plate lvi. 
Illustrating Mr. McAllister’s paper on Tetraspora lubrica. 
All figures were drawn with the aid of a camera lucida, a Zeiss apochromatic immersion lens, 
1.40 N.A., and an 18 compensating ocular (magnification about 3,000) being used in all cases except 
for Fig. 1, which has a magnification of about 1,650 diameters. 
Fig. 1. Cells drawn from living material showing localized chlorophyll-bearing area. 
Fig. 2. Cells showing nucleus in resting condition. The cytoplasm here shows no differentiation 
into chloroplastid. 
Fig. 3. A resting nucleus showing reticulum and nucleole. 
Fig. 4. An early prophase showing increase of chromatic material in the nucleus. 
Fig. 5. A later prophase. 
Fig. 6. Still later prophase with nucleole still intact. 
Fig. 7. The chromatic material has contracted to form a knot in the centre of the nuclear cavity. 
Fig. 8. A looser knot showing the presence of a spireme. The double nature of the pyrenoid is 
well shown in this figure. 
Fig. 9. The segmented spireme. 
Fig. 10. As above. 
Fig. 11. The chromosomes shortening and thickening. 
Fig. 12. Similar to Fig. 11. 
Fig. 13. Immediately before metaphase of the second division. Caps of denser protoplasm are 
to be seen at the poles of the nucleus. Thirteen chromosomes are to be identified. 
Fig. 14. Late prophase of the second division. 
Fig. 15. Metaphase of the first division. 
Fig. 16. Metaphase of the first division. 
Fig. 17. Metaphase of the second division. One a polar view with eleven chromosomes. 
Fig. 18. A polar view of the first metaphase showing thirteen chromosomes. 
Fig. 19. Anaphase of the first division. 
Fig. 20. Late anaphase or early telophase — the central spindle conspicuous. 
Fig. 21, Early telophase of the second division. 
3 B 2 
