SEGMENTATION AND DIEEEEENTTATION OF CHROMOSOMES. 297 
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EXPLANATION OF PLATES 12 and 13, 
1 llustratiiig Dr. AV. E. Agar’s iiieinoir on “Transverse Seg- 
mentation and Internal Differentiation of Cliromosonies.” 
[All figui-es were drawn with the Abbe camera, under a magnification 
of 2500 (Zeiss P5 mm. Apochr., 12 comp, oc., drawing table at the level 
of the microscope stage). In I'eproduction, all figures have been reduced 
to -f except fig. 15, which is reduced to f. Final magnification of figs. 
1-14, as reproduced, is therefore about 1875. All the figures are of 
Lepidosiren paradoxa.] 
PLATE 12. 
Fio- L — Metaphase, cut in thi’ee sections from a nerve-cell. Larva 
of Graham Kerr's stage 31 -|-. Sublimate acetic. 
Fig. 2. — Portion of a metaphase in a nerve-cell of the same larva. 
Fig. 3. — Portion of a metaphase in a nerve-cell of the same larva. 
