A Fossil Wood of Sequoia from the Tertiary of Japan . 1 
BY 
KONO YASUI, 
Assistant Professor of Botany in the Tokio Normal College. 
With Plate IV. 
T HE Aichi-Gifu coal-field, situated in the middle region of Hondo (the 
main island of Japan), belongs to the Tertiary, and the lignitic 
coal from this field contains large quantities of wood belonging for the 
most part to the Cupressinoxylon type. The identification of woods and 
even genera of living Cupressineous types, as was long ago pointed out 
by Goeppert, is extremely difficult, and in most cases quite impossible 
in view of the simplicity of organization of Cupressinoxyla . The genus, 
which can be most definitely diagnosed, is one which is characterized 
by a unique reaction to wounding. The material which I am about to 
describe fortunately shows modifications of structure, such as, in living 
material, are formed as a response to injury, and this evidence, together with 
other and normal structural features, supplies a sufficiently exact diagnostic 
description. 
Sequoia hondoensis, sp. nov. 
Gross Features. 
The wood is dark reddish brown in colour, and the annual rings 
are very narrow but quite distinct, particularly with the lens. The narrow- 
ness of the annual increments, as will be shown later, is due to a considerable 
extent to the action of fossilization on the width of the ring. Making 
allowance for the exiguity of the zones of woody growth resulting from the 
conditions accompanying lignitic transformation, it must still be conceded 
that in life the annual rings were narrow, as would be the case in the later 
development of an old tree. From the somewhat frequent occurrence 
of alternate pitting in the tracheides of our specimen, it seems not unlikely 
that it was derived from the root system of the prehistoric tree. Our 
specimen was too small and too much distorted to permit of any accurate 
inference in regard to the diameter of the trunk from which it originated. 
Traumatic resin canals reveal their presence by thin white lines running 
across the specimen tangentially in distant annual rings. 
1 Contribution from the Laboratory of Plant Morphology of Harvard University. 
[Annals of Botany, Vol. XXXI. No. CXXI. January, 1917.] 
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