948 PROFESSOR W. C. WILLIAMSON AND DR. D. H. SCOTT ON THE 
the whorls of sporangiophores, of which 5 are shown, with their sporangia. 
Note the well-preserved central cylinder of the axis. C.N. 1022. x about 8. 
Photograph 11. Part of a tangential section of the same specimen, showing the 
alternate whorls of coherent bracts, and of sporangiophores. In the former 
note the vascular bundles. The sporangiophores are seen in transverse section, 
each surrounded by its 4 sporangia. C.N. 10224. X about 8. See also 
Plate 81, figs. 27 and 28. 
Photograph 12. Transverse section passing through a whorl of coherent bracts, of 
which there are 13. Their vascular bundles can be seen. ‘The small trans- 
verse sections, seen immediately outside the whorl, are those of bract-tips 
rising up from below. They alternate with the bracts of the next whorl. The 
still smaller transverse sections, seen in some places between the larger, are 
those of extreme tips of bracts from the second whorl below. CN, 997, 
x about 20. 
Photograph 13. Transverse section passing through a whorl of 6 peltate sporangio- 
phores, some of which are shown completely, with the sporangium attached to 
the lower surface of the peltate expansion, at its edge. Here, again, the tips 
of the two whorls of bracts below are shown in transverse section surrounding 
the strobilus. C.N. 1020. x about L6. 
PLATE 74. 
Photograph 14. C. Binneyana. Transverse section of strobilus, passing through an 
internode. In the axis the stele has four prominent corners, with a bundle 
and its canal at each corner. A ring of sporangia surrounds the axis, and 
beyond these again are seen the extremities of bracts, some in section, others 
in surface-view. C.N. 10374. X about 16. 
Photograph 15. Calamostachys Casheana, Tangential section. Parts of three 
whorls are shown. All the sporangia are macrosporangia except one. The 
single microsporangium belongs to the middle whorl, and to a sporangiophore 
which also bears three macrosporangia. C.N. 1587. x about 18. See also 
Plate 82, fig. 38. 
Photograph 16. Transverse section of the same specimen. Only macrosporangia are 
shown. The central cylinder has formed some secondary wood. C.N. 1588. 
x about 25. See also Plate 82, figs. 36 and 37. 
Photograph 17. Calamostachys sp. Part of a radial section of the strobilus. The 
bracts and sporangiophores are obliquely ascending, not horizontal as in C. 
Binneyana. C.N. 1896. X about 8. 
Photograph 18. Tangential section of the same specimen. C.N. 1897. X about 8. 
