64 THE FLORA OF THE DAKOTA GROUP. 



Betulites Snowii, sp. UOV. 

 PI. V, Figs. 1-4. 



Leaves larger, subcoriaceous, loug-petioled, rhomboidal-ovate in outline, 

 pointed at apex, broadly cuneate at base, deeply, .sliarpl}-, uuecpiall}- dentate; 

 secondaries oblique, straight, or the lowest pairs slightly curved backward. 



These beautiful leaves, still of the same type as those of the preceding 

 species, differ really not only in their larger size and the greater length of 

 the petiole, but in the mode of the divisions of the borders, which are cut 

 into unequal, longer, more acute teeth, separated by deeper, half-round 

 sinuses. The petiole, as seen in PI. V, Fig. 1, is slender, 6"'" long, and the 

 leaf lO''" long and T"^ broad. In the specimens sent for examination by the 

 Museum of the University of Kansas a number of leaves of the same size, 

 form, and characters have been observed. 



Habitat: Ellsworth County, Kansas. Nos. 593, 771, 340 and 290 of 

 the museum of the University of Kansas ; E. P. West, collector. 



Betulites populifolius, sp. uov. 

 PI. VI, Figs. 1, 2. 



Leaves large, coriaceous, long-petioled, cordate or ovate in outline, 

 pointed at apex, truncate at base and deflexed to the i)etiole, regularly 

 denticulate; secondaries deep and strong, parallel and equidistant, the 

 lowest pair opjjosite and ramose. 



One of the leaves, which is 7""" long and as broad below the middle, 

 has a petiole 5.5™ long ; the other is small, rather ovate, inequilateral, but 

 appears identical, especially on account of the thickness of the secondaries. 

 Hut both are really of the same type and have the essential characters of 

 those described under the name of Betulites JVestii. The appearance is, 

 however, far different. The texture is thicker, the nervation stronger, and 

 the border teeth are all equal and equidistant. By the divisions of the 

 l)()rders the leaves are related to species of Grewiopsis, especially to G. 

 II(ii/(hmi Lesq.,^ and also to a peculiar form of I'hitanas Newheiriana Heer.^ 

 Fig. 2 is even like other forms of Betulites. Its shape as well as its nerva- 

 tion is remarkably similar to that of Betula vetusta Heer' of the Patoot Flora. 



Habitat : P]llsworth County, Kansas. No. 6 of the collection of the 

 museum of the University of Kansas. Collected by A. Wellington. 



' Cret. Fl., p. 97, PI. iii, Figs. 2, 4 ; PI. xxiv, Fig. 3. 

 "Fl. Fo88. Arct., vol. 7, PI. lix, Fig. G. 

 ^Fl. Foss. Arct., vol. 7, PI. lv. Figs. 7,7a. 



