— 583 — 
medullary rays which are more often partially biseriate and whose 
‘ cells are less rounded, and by the round, usually a little distant, 
areoles, very rarely biserjate, with small round pores. 
Locality : Road between Mr. Brun’s and S. Rafael, Rio Grande 
do Sul. Fossil wood in red shales 100-200 meters above coal beds. 
Lot. 3918. The type is BR 23. 
Dadoxylon meridtonale n. sp. 
Pl. xiv. Figs. t-% 
Secondary rylem laminae fairly regular and of moderate widti ; 
tracheides long, acute, regular, but slightly undulate, transversely 
small, rather thick-walled polygonal and variable in cross-section, 
the radwal diameter being yenerally equal to or « little greater than the 
tangential diameter, which averages about 264; medullary rays, 
numerous, close, 1-6 tracheides distant on the sane transverse line, 
narrow, 1-30 or more cells in height, usually uniseriale, rarely bise- 
riate for the height of 1-5 cells ; ray cellsmore or less distinctly sub- 
round or oval in tangential section and a litlle higher than wide, 
averaging about 25 pin height. and in radial section, angular, ye- 
nerally subtending 4o0r 5 tracheides, and slightly narrowed towards 
the ends ; areoles strictly uniseriate, relatively large, distinctly 
broader than high, averaginy about /3 u in transverse diameter, 
usually contiguous, sometines a litte crowded longitudinally, and 
traversed by oblique oval pores. 
The sections represented in part in Plate xiv, were cut from a 
brownish fragment 6cm. long, 8cm. in radial, and 5 cm. in tangential 
diameter. 
As indicated by the parallelism of the rays the specimens must 
have been derived from a tree probably as much as 50cm. in diameter. 
The tangential section, Fig. 3, is from the peripheral side of the 
fragment. Both the cortex and the inner part of the xylem cylinder, 
including the pith, are wanting. The reference of the genus Dadoxylon 
is therefore subject to doubt. 
Notwithstanding the partial disintegration of the tissue in por- 
tions of the slides the preservation is in other parts very imperfect. the 
cell membranes being quite distinct. The bacteria, which seem to 
