68 ROYAL SOCIETY OF CANADA 
The radial section shows the bordered pits to be hexagonal in 2-4, 
chiefly 3 rows. The elements of the medullary rays are all of one kind, 
and their lateral walls bear from 2-4, chiefly about 4 pits per tracheid. 
These pits are commonly disposed in radial series. 
In tangential section the rays are seen to be 1-2 seriate. 
Transverse.—Tracheids about 47 x 56 mic. broad, the walls 9.3 mic. thick. 
Growth rings none. 
Radial.—Bordered pits numerous throughout the tracheids, in 2-4, chiefly 3 
rows, about 12 mic. broad. Ray cells equal to about 3-4 tracheids; 
the lateral walls with oval pits, 2-4, chiefly 4 per tracheid and dis- 
posed in radial series. 
Tangential.—Rays of medium height, 1-2 seriate in part, the oval cells chiefly 
about 25-37 mic. broad. 
CORDAITES ANNULATUM, Dn. 
Bib. :—Quart. Jn’1 Geol. Soc., 1886, 146; Knowlton, Foss. Woods & Lig. of the 
Pot. Form., 1889, 52, and Proc. U. S. Nat. Mus., XII., 1890, 610; Can. 
Nat., VIII., 1863, 433. 
Dist.—Middle Carb. of the Joggins, N. S. 
The original description of this species in 1863, was derived from 
a specimen six inches in diameter, which is described as having about 
fourteen to sixteen growth rings and a pyritised pith about one inch in 
diameter.* 
A critical examination of the original specimen shows that there is 
nothing of the nature of growth rings, but as the description states, 
there are “layers of structureless coal representing cellular tissue or 
very dense wood.” These layers run diagonally to the radial lines in 
which the tracheids fall, and therefore diagonally to the medullary rays, 
but sooner or later they curve in such a manner as to often become more 
or less parallel with them. It will thus be observed that it is quite im- 
possible for them to represent growth rings. The alternating layers of 
badly preserved wood have been taken for the summer wood of the 
growth rings, but in following out one of these for a long distance 
radially, no evidence of growth rings appears. It would thus seem that 
the statement of the first diagnosis was based upon a misinterpretation 
of the features resulting from decay localised along diagonal or radial. 
lines. The confusion resulting from this has led recent observers to 
question if this plant has any real affinity with Cordaites,? but although 

1 Can. Nat., VIII. 1863, 433. 
? Proc. U. S. Nat. Mus., XII., 1890, 410. 

