386 GEOLOGICAL SURVEY OF THE TERRITORIES. 



a long slender petiole, with very entire borders ,• three to five nerved 

 from the top of the petiole. 



A very fine species, with leaves scarcely variable in size, 3 cent, long 

 and at least as broad. The three i)rimary veins ascend from the top of 

 the petiole to three-fourths of the leaves, branching outside and anas- 

 tomosing with branches of a second or marginal pair of veins which 

 ascend only to half the leaf. The texture of these leaves is somewhat 

 thick, subcoriaceous. They are generally found on the same specimens 

 with Palkirus Columbi, Heer, which tbey resemble. The slender petiole 

 is nearly as long as the leaves. This species is distantly related to some- 

 small varieties of Fopuliis arctica, Heer. 



POPULUS ATTENUATA, Al. Br. 



The same form as already published, Am. Jour. Sci. and Arts, (1868,) 

 p. 205. It is found at Carbon both above and below the main coal. 



POPULTJS MUTABiLis, var. CRENATA, Heer. 



Our specimen represents an entire leaf agreeing in form and nervation 

 with Goppert's, Fig. 2 of PI. XVI, iil Schossnitz Flora. In the Carbon 

 leaf, however, the teeth of the borders are large, sharply pointed out- 

 ward, or less turned upward. This difference is not specific. 



Alnus Kepersteinii, Gopp. 



The same form as described in Eept. 1871, p. 292, from Evanston. 

 The borders of the leaf, however, appear merely undulate as in Lud- 

 wig's Pal., Vol. VIII, PI. XXXII, Fi 



Betula Stevensoni, Lsqx. Eept., (1871,) p. 293. 



Already published like the former from Evanston, where the species 

 is abundant. It is not as common at Carbon, but represented in very 

 good specimens. 



QuERCUS PLATANiA, Hecr, Arct. Fl., p. 109. 



Leaf membranaceous, broadly ovate, rounded to the base in broad . 

 auricles, with distantly dentate borders ; pinnately nerved ; secondary 

 veins numerous, craspedodrome. 



There i« in the collection a beautiful leaf of this species which some- 

 what diii'ers from the •description of the author, as it is made in 

 the 1st vol. of the Arct. Fl., but exactly agree with the fine leaf of this 

 species figured in Vol. II, PI. XLVI, Fig. 5, of the same work. This one 

 is nearly an exact representation of ours, and, too, has the point de- 

 stroyed. It is 13 cent, wide above its base, the borders marked by short 

 somewhat distant teeth; the lower lateral veins opposite, diverging 30° 

 from the medial one, the other pairs at a short distance from each other, 

 alternate, parallel, with a thin lateral basilar veinlet going out at right 

 angle from the medial nerve, just under the lowest pair of secondary 

 veins. These are much branched outside ; the ux)per ones branch once 

 or twice near the borders. This leaf has the characters of a Flatanus, 

 and I was inclined to consider it as different from Heer's species on 

 account of the difference in the denticulation. But in his description 

 of a specimen from Spitzberg, the author remarks, p. 57, that the differ- 



