[PENHALLOw] CRETACEOUS AND TERTIARY PLANTS OF CANADA 69 
fragment of a branch, which it eventually proved to be. The details 
of its examination are as follows :— 
Transverse. (Fig. 17.) Growth rings prominent; the spring wood 
passing gradually into the summer wood. Resin canals rather abun- 
dant and scattering, the details of structure not recognizable. 
Radial. (Fig. 18.) Tracheids highly altered by decay and 
maceration; spiral structure of the wall conspicuous but due to 
extreme development of the striation through maceration, the normal 
spirals of secondary growth not recognizable; bordered pits nearly 
obliterated, in one row. Details of structure in the medullary rays 
are nearly obliterated; pits on the lateral walls about 4 per tracheid, 
bordered ? 
Tangential. (Figs. 19 and 20.) The structure shows extreme 
alteration through decay. The medullary rays of the uniseriate 
type have round or oval cells about 24-5 broad; those of the fusiform 
type have thick-walled cells and in their general structure are com- 
parable with those of Tsuga, Picea and Pseudotsuga. 
There can be no doubt that this specimen represents the wood 
of Pseudotsuga, and it thus acquires additional interest because it is 
the first instance of which I am aware, of the occurrence of this genus 
in the Miocene, or of even later formations, though it is a matter of 
some surprise that it has not long since appeared in the great 
abundance of material collected from the Tertiary deposits of the 
western portion of this continent, where it is now so conspicuous an 
element of the forests. 
PINUS TRUNCULUS, Dn. 
Jawson, Trans. R. Soc. Can. (1890), VIII., iv., 78. 
This species was first described by Sir William Dawson on the 
basis of a single leaf from the Lower Miocene of the Similkameen 
Valley at Stump Lake, B.C., and it now reappears in the Miocene of 
the Horsefly River. 
CASTANEA CASTANZ FOLIA (Ung.), Kn. 
Lesquereux, Cretaceous and Tertiary Floras, VIII. (1883), 246, Pl. LII., 1, 3-7. 
Heer bhi rans © laxeexe 47 Only ANNE TES elu Vel (1889): 
The specimens from the Horsefly River represent fragments of 
leaves only, but they are to be identified without doubt, with Castanea 
castanefolia. 
