Barber . — Cupressinoxylon vec tense. 333 
the principal groups of Pinus and a certain number of species 1 . 
Under Cupressinoxylon , the genera Sequoia , P hyllodadus) 
Ginkgo , Taxodium and Glyptostrobus are said by different 
authors to possess characters by which they may be separated 
from all others 2 . A more careful study of the structure of 
gymnospermous wood might have placed this group between 
the Angiosperms and the Cryptogams instead of with the 
Dicotyledons as was done at first 3 , just as Mercklin separated 
Sequoia from the Taxaceae on account of its wood-structure 
at a time when it was regarded as a member of that group 4 , 
and as Kraus detached Dammar a from Cunninghamia 5 . 
In spite of the fact that the woods grouped under Cupres- 
sinoxylon are drawn from such widely different groups of 
Coniferae, there is a truly remarkable similarity in their 
structure. Thus Kraus mentions forty-six species of recent 
Conifers, belonging to various groups, with woods of this type 
which he states are indistinguishable. This is the more to 
be regretted because the bulk of fossil Coniferous woods 
from the Jurassic to the Tertiary periods, and especially 
the enormous numbers found in the Brown Coal, belong to 
Cupressinoxylon. 
The earlier workers do not appear to have appreciated 
these facts, and their diagnoses were lamentably meagre. 
They do not, moreover, appear to have had any adequate 
knowledge of the process of petrifaction, nor were they 
aware of the differences existing as regards wood -structure 
between different parts of the same plant. Branches, roots, 
stems, portions altered by chemical action or undergoing 
decay, were accordingly described as separate species, so 
that Kraus, in his analysis of work previous to 1864, ventured 
the extraordinary assertion that all Cupressinoxyla described 
1 Schimper, Traite de Paleontologie vegetale. 
2 Schmalhausen, Beitr. zur Tert. FI. Siidwest-Russlands, Pal. Abh., Dames und 
Kayser, i, 1884. See also Kraus, Schroeter, Schenk in Zittel, and Goppert, 1. c. 
3 Knowlton, Fossil Woods and Lignite of the Potomac Formation, Bull. No. 56, 
U. S. Geological Survey, 1889. 
4 Mercklin, Palaeodendrologikon Rossicum, St. Petersburg, 1855. 
5 Kraus, 1. c. 
