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EXPLANATION OF PLATES VIII-XII. 
Illustrating Miss Digby’s paper on the Archesporial and Meiotic Mitoses of Osmunda. 
All the figures were drawn with a camera lucida under a 2 mm. apochr. Horn. imm. Zeiss N.A. 1-40 
with comp. oc. 18 x about 2250. 
For the photomicrographs on Plate XII I am indebted to Mr. W. B. Randles, B.Sc. 
Figs. 1-24. Archesporial Divisions. 
Figs. 25-34. Interkinetal Stages. 
Figs. 35-88. First Meiotic Division. 
Figs. 89-100. Second Meiotic Division. 
Fig. 1 01. Sporangium containing nuclei in widely separated stages (photomicrograph). 
Figs. 102-6. Synangia (photomicrographs). 
Osmunda palustris. Figs. 4, 16, 19, 25, 26, 27, 28, 62, 63, 64, 65, 79. 
O, palustris var. undulata. Figs. 22, 60, 61, 67, 68, 69, 71, 72, 73, 74, 102, 103. 
O. regalis. Figs. 32, 48, 82. 
0. palustris var. aurea. All the remaining figures. 
ABBREVIATIONS. 
1. Fixatives. A.A. = Acetic Alcohol ; H. = Hermann ; S.C. = Strong Chromic ; S.F. = Strong 
Flemming ; S.M. = Strong Merkel ; W.F. = Weak Flemming. 
2. Areas of Nucleus. E. = East ; N. = North ; N W. = North-West ; S. = South ; SE. = South- 
East; SW. = South-West; W. = West. 
O 
