Mother-cells of Smilacina racemosa (A.), Desf. 481 
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EXPLANATION OF PLATE XXII. 
Illustrating Miss Woolery’s paper on Meiotic Divisions in the Microspore Mother-cells 
of Smilacina racemosa (L.), Desf. 
All figures were drawn from sections with the aid of the Abbe camera lucida with Zeiss 
apochromatic immersion 2 mm. apert. 1*40, and compensating ocular 12. Magnification about 
1750 to 1800. 
Fig. 1. Resting nucleus of the microspore mother-cell, showing typical structure of nucleus and 
cytoplasm. 
Fig. 2. Resting nucleus with slightly larger chromatin granules. Some portions of threads 
lying parallel. 
Fig. 3. Tangential view, showing larger lumps of chromatin. Some portions of the linin thread 
have been drawn in. 
Fig. 4. Tangential view of stage similar to Figs. 1, 2, and 3. 
Fig. 5. Chromatin thread beginning to contract and to become more uniform in diameter. 
Fig. 6. Enlargement of nuclear cavity and contraction of nuclear contents. Strands are 
connecting chromatin with the nuclear membrane. 
Fig. 7. Chromatin contents much contracted and nuclear cavity much enlarged. Strands 
extend from chromatin to nuclear membrane. The cell-wall is somewhat thickened. 
Fig. 8. A typical tight synaptic ball. 
Fig. 9. Nucleus, showing untangling of synaptic ball, with thread of almost uniform thickness. 
Fig. 10. Slightly older stage. Several cut ends are visible. Figs. 9 and 10 are drawn from 
adjoining nuclei in the same loculus. 
Fig. 11. Tangential view of nucleus just after synapsis, showing looping and twisting of thread. 
Fig. 12. Tangential view similar to Fig. 11. The thread is much narrower than in most nuclei 
at this stage. 
Fig. 13. Untangling not yet complete. Many cut ends are shown. Thread of uniform 
diameter. 
Fig. 14. Typical spireme stage. Relatively few cut ends to be found. 
