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carian or the Taxodinian divisions of the Pinaceae, the evidence fa- 
voring the Voltzian group. Especial search should be made for cones, 
no fragments of which are present. 
Locality : Northeast of Minas, Santa Catharina. Plant bed 55 
meters above the granite of 225 meters below the Iraty black shale. 
Lot, 39214: 
Dadoxylon 
Enddlicher, Synopsis Coniferarum, 1847, p. 298. 
The generic name Dadoxrylon is now generally applied to the Pa- 
laeozoic representatives of a coniferous type of wood exhibiting an 
anatomy closely comparable to that of the living Araucaria or Dam- 
mara. 
The xylem is formed centrifugally, the radially arranged tra- 
cheides being punctuate on their radial walls wilh generally pluri- 
seriate and contiguous bordered pits, which are sometimes a little 
distant but often crowded, in which case they are hexagonal. The 
pores are generally obliquely oval or elliptical. 
The genus is now broadly and comprehensively construed so as 
to include most of the Palaeozoic coniferous types of wood which have 
no primary or centripetal wood and which are not correlated with Cor- 
daites by the presence of a very large transversely chambered pith. 
The post-Palaeozoic woods corresponding to Dadoxvylon are placed in 
Araucariozylon Kraus, 
Fossil woods referred to Dadoxylon are found in rocks as old as 
the middle Devonian. In the older types the punctations are some- 
times in as many as four rows, and even in groups (Dadoxylon 
Newberry). 
I-vidence of rings of annual growth is very rare in all but 
the later Carboniferous and Permian types, and in these somewhat 
exceplional cases it may, im many instances at least, be due to 
reproductive or resting stages, rather than the marked climatic 
changes. 
