76 ROYAL SOCIETY OF CANADA 
PITYOXYLON CHASENSE, D. Sp. 
This material was obtained by Prof. Prosser from the Chase Forma- 
tion (Permian) at Coon Creek, Chase Co., Kansas, in 1897. The 
structure is fairly well preserved. Its chief feature is to be found 
in the occurrence of broad rays which bear a small, central resin canal. 
This feature is exhibited by my sections in tangential section only, pro- 
bably in consequence of the special condition of preservation. It 
nevertheless serves to definitely separate the plant from Cordaites, and 
its affinities are rather with the Pityoxylon of Kraus.! 
Transverse.—Tracheids chiefly in regular radial rows, very variable in size, 
squarish, about 44 x 44 mic. broad; the walls 12.5 mic. thick. 
Medullary rays numerous, chiefly one cell wide, occasionally 2-3 
seriate. Growth rings wholly wanting. Resin cells and resin 
canals not represented. 
Radial.—Ray cells all of one kind; straight, equal to 2-4 tracheids; the upper 
and lower walls thin and not pitted; the terminal walls thin, not 
pitted, straight or curved; the structure of the lateral walls not 
determinable, but the pits are probably round. 
Bordered pits in 1-3 rows, chiefly 2 rows, round or hexagonal, 
12.5 mic. broad, the orifice probably round. 
Tangential.—Rays of two kinds. 
(1) Uniseriate rays, the cells oblong, 25 mic. broad, often 2-seriate 
in part. 
(2) Fusiform rays, the terminals linear and of the structure of 
the uniseriate rays; the central tract very broad, nearly round; the 
cells large, thin-walled, irregular and enclosing a small, central resin 
passage with large epithelium cells. 
CUPRESSINOXYLON CHEYENNENSE, n. Sp. 
A specimen of the Prosser collection obtained from the Cheyenne 
(Comanche Cretaceous), east of Stokes Hill, Kiowa and Baker Co. line, 
Kansas, 1897. 
Transverse.—Tracheids in regular, radial rows, rather uniform, roundish, 
about 62 x 62 mic. broad; the walls 15.5 mic. thick. 
Resin passages and special resin cells wanting. 
Growth rings apparent, very broad, in a radial extent of 20 mm., 
two growth rings of an equal thickness of 10 mm. are represented. 
The summer wood conspicuous, about 3-4 cells thick, the tracheids 
about 29 x 38 mic. broad, the tangential walls about 15.5 mic. thick. 
Radial.—Ray cells all of one kind, straight; the upper and lower walls thin 
and not pitted; the terminal walls thin and not pitted, straight or 

1 Schimper, Pal. Veg., 370. 

