396 
Watson- — On Mesostrobus, a New Genus of 
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— (’98) : Ibid. II — Spencerites. Phil. Trans. B. clxxxix, pp. 83-106. 
— (’08): Studies in Fossil Botany, i. London. 
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EXPLANATION OF PLATE XXVII. 
Illustrating Mr. Watson’s paper on Mesostrobus. 
All the figures are untouched photographs. Phot. 1 by Flatters and Garnet, Manchester, the 
rest by the Author. 
Phot. 1. A complete transverse section of the cone of Mesostrobus Scottii , sp. nov. This gives 
a good general idea of the build of the cone. At a are seen two sporophylls cut so near to the 
axis that the sporangia are not yet attached. This section also indicates the distribution of the 
sclerized patches in the outer cortex. R. 1122. 3. Manchester Museum Collection, x 6-i. 
Phot. 2. Transverse section of the ‘bud’ at the tip of the cone. At par will be seen the two 
patches of parichnos in a leaf-base. R. 1122. 1. Manchester Museum Collection, x 15. 
Phot. 3. The axis of the section represented in Phot. 2 enlarged. Shows the wood xy., the 
concentration of the leaf-traces l.t. in the zone of the inner cortex and Phloem, which are in this 
section defective, some remains of the middle cortex, and the outer cortex with the leaf-trace, 
surrounded by its parenchymatous sheath passing out through a hole in a sclerized patch of the outer 
cortex. R. 1122. 1. Manchester Museum Collection, x 45. 
Phot. 4. A portion of the original of Phot. 1 enlarged. Shows the wood xy., phloem ph ., and 
inner cortex i.c., and the middle cortex m.c., quite well preserved. The photograph shows also the 
insertion of three sporophylls, to none of which is a sporangium attached ; the one shown completely 
in the photograph is the section cut furthest from the centre to which a sporangium is not attached, 
and I think from the form of the upper surface, which it must be remembered is cut obliquely, so that 
all projections appear much magnified, is very near the point where the sporangium becomes attached 
to the sporophyll. R. 1122. 3. Manchester Museum collection, x 26. 
Phot. 5. A transverse section showing a sporophyll with a sporangium attached. R. 1122. 2. 
Manchester Museum Collection, x 18-3. 
