Cretaceous Pine Leaves, 
401 
(3) ‘ In the probable absence of an endodermis.’ The Japanese fossil 
is seen to have a particularly well developed endodermis. (4) ‘ In the 
absence of infolding of the walls of the mesophyll.’ The Japanese species 
has excellently preserved cells showing deep infolding of the cell-walls 
of the mesophyll. 
It is clear, therefore, that the new species approximates extremely 
closely to the living type, and judging from the foliage, can be no more 
than specifically distinct from any living species. In the shape of the leaf, 
which is oval, with no straight edge such as is found in the Pines usually, we 
see a suggestion that there may have been only one leaf in the fascicle. 
The living P. monophylla is more circular in outline, however, and we would 
do no more than point out the suggestion offered by the shape of the leaf 
in P. yezoensis and note that it is also supported by the fact that there 
is a single bundle in P. yezoensis , as there is in P. monophylla , while there 
is usually a double one in the modern Pines with two or three needles in 
a fascicle. 
These two new species from the Cretaceous show that the modern 
type of leaf in Pines was evolved by that time, and that at the same time 
and in the same place were living trees with the older type of Prepinus 
foliage. 
We wish to tender our thanks to the Director of the Royal Gardens, 
Kew, for the supply of living species of Pine leaves which he kindly 
provided for comparison with the fossils. 
Papers quoted. 
Hollick, A., and Jeffrey, E. C. (’ 09 ) : Studies of Cretaceous Coniferous Remains from 
Kreischerville, New York. Memoirs of the New York Botanical Garden, vol. iii, pp. 1-76, 
PI. I-XXIX, New York, May, 1909. 
Jeffrey, E. C. (’ 08 ): On the Structure of the Leaf in Cretaceous Pines. Ann. Bot., vol. xxii, no. 
lxxxvi, pp. 207-20, PI. XIII and XIV, Oxford, 1908. 
Stopes, M. C. (’ 03 ) : On the Leaf-Structure of Cordaites. New Phytol., vol. ii, pp. 91-8, PI. IX, 
London, 1903. 
Stopes, M. C., and Fujil, K. (’ 10 ): Studies on the Structure and Affinities of Cretaceous Plants. 
Phil. Trans. Roy. Soc., vol. xx b, pp. 1-91, PI. I-IX, London, 1910. 
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