358 
= 
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NEW SPECIES OF PERMIAN OSMUNDACEZÆ, 
EXPLANATION OF THE PLATES. 
PLATE 32. 
Thamnopteris Kidstoni Zalessky. Transverse section of the upper part of the 
specimen. x 24. 
Thamnopteris Kidstoni Zalessky. Part of a transverse section of the peripheral 
region of the stele and of the inner cortex. owy., outer xylem ring; æy.sh., xylem- 
sheath; p4., phloem ; en., endodermis; 7.C., inner cortex. x 50. 
Thamnopteris Kidstoni Zalessky. Portion of a longitudinal section of the central 
and outer xylem of the stele. ewy., central xylem; o.cy., outer xylem. x 50. 
Thamnopteris Kidstoni Zalessky. Transverse sectioa of a leaf-trace in proximity to 
the stele. X, outer xylem ring ; pA.. phloem; 7.C., inner cortex. Xx 25°5. 
Thamnopteris Kidstoni Zalessky. Transverse section of a leaf-trace in the peripheral 
part of the inner cortex. x 255. 
Thamnopteris Kidstoni Zalessky. ‘Transverse section of a leaf-trace in the sclerotic 
cortex, x 2575. | 
PLATE 33. 
Thamnopteris Gwynne- Vaughani Zalessky. Transverse section. x 24. 
Thamnopteris Gwynne- Vaughani Zalessky. Part of a transverse section of the 
peripheral region of the stele. o.xy., outer xylem ring; ph., phloem. x 50. 
Thamnopteris Gwynne-Vaughani Zalessky. Part of a longitudinal section of the 
central and outer xylem of the stele. e.ry., central xylem; ovy., outer xylem. 
x 50. | 
Thamnopteris Gwynne-Vaughani Zalessky. Transverse section of a leaf-trace in 
proximity to the stele. en., endodermis; 7.C., inner cortex. x 25/5. 
Thamnopteris Gwynne- Vuughani Zalessky. ‘I'ransverse section of a leaf-trace in the 
peripheral part of the inner cortex. s.0., sclerenchymatous cortex. Xx 25:5. 
Bathypteris rhomboidea Kichwald. Transverse section of a portion of the stele. 
cry, central xylem; o.ry., outer xylem ring. x 50. 
Bathypteris rhomboidea Kichwald. Transverse sections of leaf-traces in proximity 
to the stele. x 95:5. 
Prark 34. 
Figs. 1-3. Zalesskya uralica Zalessky. Fig. 1, transverse section, nat. size. Fig. 2, trans- 
verse section of the peripheral part of the stele and the adjacent inner cortex, 
X 255. Fig. 3, transverse section of the peripheral part of the stele. x 50. 
o.ry., outer xylem ring; «y.sh., xylem-sheath ; ph. phloem. 
Figs. 4-5. Zalesskya gracilis Kidst. & Gwynne-Vaughan. Fig. 4, transverse section of 
> 
Figs. 6- 
peripheral part of the stele and adjacent part of the inner cortex. x 255. 
Fig. 5, transverse section of the peripheral part of the stele. x 50. 
tY., outer xylem ring; zy.sh., xylem-sheath ; ph., phloem. 
Thamnopteris Kidstoni Zalessky. Portions of the central part of the stele in 
transverse and longitudinal section. x 97. cvy., central xylem; ovy., inner 
part of the outer xylem ring; p.c., the cells with brown contents are parenchy- 
matous (the “ primitive fibres " of C. E. Bertrand). 
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