103 
ateral dentate teeth. Length ranging from 8 cm. to 12 cm., maximum 
width from 3-25 cm, to 5 cm. Petiole long and stout, expanded proximad, 
2 cm. to 3 cm. in length. Midrib stout, prominent on the under side of the 
leaf. Secondaries about 9 subparallel, camptodrome pairs; sending small 
curved branches to the marginal teeth. Tertiaries thin, largely percurrent. 
This is an exceedingly well-marked species of cottonwood, with per- 
haps a slightly shorter petiole than the existing forms. It resembles some- 
what the existing Populus balsamifera Linn., but is narrower and more 
elongate. It is exceedingly like the existing Populus acuminata Rydberg, 
which resemblance has suggested its specific name. The former is a stream 
bank type, now found in the Rocky Mountain foothills from Alberta to 
southern Colorado. The fossil species comes from Joseph creek. 
Order, Fagales 
Family, bettjlaceae 
Betula heterodonta Newberry 
Plate XVI, figure 5 
Betula heterodonta Newberry, U.S. Nat. Mus. Proc., vol. 5, p. 508, 1882; 
U.S. Geol. Surv., Mon. 35, p. 64, PI. 44, figs. 1-4, PI. 45, figs. 1, 6, 
1898; Knowlton, Idem., Bull. 204, p. 40, 1902; Penhallow, Rept. 
Tert. PI. Brit. Col., p. 39, 1908. 
Betula grandifolia Heer (not Ettingshausen), FI. Foss. Arct., Bd. 2, abt. 2, 
p. 29, PI. 5, fig. 8, 1869. 
This species was described by Newberry from the Upper Clarno beds 
of Oregon, and it has been reported from Tranquille river and Quilchena, 
B.C. To it should be referred the form from the Kenai formation of 
Alaska which Heer identified as Betula grandifolia Ettingshausen, 1 a dis- 
tinct and later species. Penhallow remarks, of the British Columbia 
occurrences cited above, that as the type came from the Miocene of Oregon 
it tends to prove the Miocene age of the former deposits. This is an error 
as the Bridge Creek beds of Oregon are definitely known to be of pre- 
Miocene age. This species occurs in the collection from Newhykulston 
creek and in the collection from Kitsilano, 
Betula parvifolia Berry n. sp. 
Plate XV, figures 1-3 
Orbicular to elliptical, nearly equilateral leaves of variable size and 
form, mostly small, about equally rounded at the apex and base. Margins, 
except near the base, beset with small, even, dentate teeth. Length rang- 
ing from 2 • 25 cm. to 3 • 75 cm. Maximum width, midway between the apex 
and the base, ranging from 1*5 cm. to 2-6 cm. Petiole stout, curved, 
4 mm. to 8 mm. in length. Midrib stout. Secondaries 7 or 8 pairs, stout, 
craspedodrome, giving off a curved craspedodrome tertiary from the out- 
side near their tips. Internal tertiaries percurrent. 
1 Ettingshausen, C. v., Foss. FI. v. Bilin, p. 125, PI. 14, figs. 23, 25, 1867. 
