On the Affinities of the Genus Yezonia. 1 
BY 
EDWARD C. JEFFREY, 
Professor of Plant Morphology in Harvard University. 
With Plate LXV. 
R ECENTLY Dr. Marie C. Stopes of the University of Manchester and 
Professor K. Fujii of the University of Tokio have published an ex¬ 
tensive monograph on the Cretaceous plants of Hokkaido, Northern Japan. 
Amongthe remainsdescribed are species of Pteridophyta, Gymnosperms, and 
Angiosperms. The present communication has to do with one of the 
Gymnospermous species published by these authors, viz. Yezonia vulgaris , 
of which they state that 1 it is impossible to find any family among the 
Gymnosperms with which we can satisfactorily include this plant. That it 
is a Gymnosperm is proved by the character of the wood of the main axis, 
by the guard cells of the stomates, as well as by a variety of minor characters.’ 
It will be the aim of this article to show that Yezonia represents the un¬ 
recognized twigs of one of the commonest of the Mesozoic Conifers and 
that its affinities are with the Araucarineae. This state of affairs would in 
all probability have been recognized by the Anglo-Japanese authors had 
they been able to study the external form as well as the internal structure 
of their material. Unfortunately the condition of the material, which 
occurs in the form of nodules, and the methods adopted by these investi¬ 
gators made such inference difficult. 
It will be well to describe in some detail the internal structure of the 
Jurassic and Cretaceous genus Brachyphylimn, especially in regard to the 
peculiarities of structure emphasized by Stopes and Fujii as characteristic 
of their supposed new genus Yezonia. 
External Form. 
Figures of the superficial appearance of B r achyphy llum are common 
in all memoirs dealing with Upper Jurassic and Cretaceous plants. The 
reader may be referred to the recent memoir of Dr. Arthur Hollick and the 
writer for a representation of a species common in the Cretaceous deposits 
1 Contributions from the Phanerogamic Laboratories of Harvard University, No. 35. 
[Annals of Botany, Vol. XXIV. No. XCVI. October, 1910. 
