[PENHALLOW] NORTH AMERICAN SPECIES OF DADOXYLON 69 
badly preserved, we may say without hesitation, that enough characters 
are recognisable to eliminate all reasonable doubt on this point. 
Transverse.—Structure much altered by decay, extensive areas being com- 
pletely carbonised and consolidated to coal. The tracheids are 
about 34 x 44 mic. broad, the walls much attenuated by decay. 
Radial.—Structure of the rays not determinable. 
Bordered pits hexagonal, 9.5 mic. broad, in 2-3, chiefly 2 rows. 
Tangential.—The structure is too much altered by decay and pressure to 
make the details obvious. 
CORDAITES MATERIARIUM, Dn. 
Figs. 13, 14, 17. 
Bib. :—Dawson, Rept. on the Geol. Struct. of P. E. Island, 1871, 42; Can. Nat., 
VIII., 1863, 483; Acad. Geol. ed. 3, 1878, 473; Quart. Jn’l Geol. Soc., 
XXITL, 1866, 96, 127, 128, 141, 145: Quart. Jn’l Geol. Soc., 1874, 215, 
216; Can. Rec. Sc., I., 1885, 158; Grand’Eury, Geol. et Pal. du Bass. 
Houil. du Gard., 1890, 316; Proc. U. S. Nat. Mus., XII., 1890, 608. 
Dist.—Holmes Co., Ohio (Newberry) ; Upper Coal Measures of Malagash, 
Pictou, Joggins, Belen and Cambon, N. S.; St. Georges Bay, New- 
foundland; Mirimichi, N. B.; Glace Bay, C. B.; Marion Co. Illinois. 
The original description of this species, based upon material from 
the middle and upper coal measures of the Maritime Provinces, was pub- 
lished in 1863.1 It compares the structure of the wood to that of C. 
Brandlingii, notes the occurrence of a Sternbergia pith, and records the 
occurrence of the plant in the sandstones of the upper coal formation, 
where it is represented by vast numbers of trunks. 
The only notable feature of this species appears in the character 
of the pits on the lateral walls of the ray cells. These structures show a 
very narrow border as in the Sequoias, but in many cases this element 
is so reduced as to become obscure, when the pit is reduced to the con- 
dition of a simple, open pore, such as occurs so commonly in many of 
the soft pines. At first this was attributed to loss of material by grind- 
ing, but a very searching examination proved it to be a normal feature. 
In C. materioides, the border is always more prominent, but the pore is 
nevertheless very wide, and the whole pit bears a marked resemblance 
to those found in Sequoia. 
Transverse.—Tracheids 45 x 75 mic. broad, the walls 7.8 mic. thick.” Scatter- 
2 The normal thickness of the walls in this genus may be taken as 12.5 
mic. Anything less indicates the operation of decay. 
