306 GEOLOGICAL SURVEY OF THE TEREITOEIES. 



ined. Lignitic Flora. la this, the secondary viens are, however, more 

 oblique and more distant. It may be a mere local variety. 

 Habitat. — Point of Eocks, Br. F. V. Hay den. 



25. Viburnum Wymperi, Heer. 



This species has been described in Dr. F. V. Hay den's Eeport for 1873, 

 p. 382, and referred, with some doubt, to the Greenland species described 

 in Arct. Flor. (II, p? 475, PI. XLVI, hg. P). The secondary veins iu our 

 species are more distant and less regularly parallel. Though its rela- 

 tion to the arctic species is somewhat doubtful, it does not show any 

 difference w-hatever from that of Black Butte. 



Habitat. — Point of Eocks, JDr. F. V. Hayden. 



26. Virburnum marginatum, Lsqx. 



The specimen is fragmentary, but the species, very common at Black 

 Butte, is recognizable. 

 Habitat. — Poiut of Eocks, Wm. Cleburn. 



27. DiosPYROS BRACHYSEPALA, Al. Braun. 



Described already in Dr. Hay den's Eeport for 1872 (p. 394), from spe- 

 cimens of Black Butte, and in Eeport for 1873 (p. 401), from specimens 

 of Sand Creek, Colorado, a locality identified with Golden by its flora. 

 But none of the leaves found as yet are as well preserved and as well 

 characterized as that of Point of Eocks, which is especially comparable 

 to the leaves in Heer's Fl. Tert. Helv. (PI. CII, fig. 2). The species is 

 not rare in the Miocene of Europe, especially in the lower groups, and 

 appears equally widely distributed iu our Lower Tertiary. 



Habitat. — Point of Eocks, Br. F. V. Hayden. , 



28. Greviopsis Cleburni, sp. nov. 



Leaves of medium size, subcoriaceous, ovate, rounded, and narrowed 

 by an inward curve to the short petiole, sinuato-denticulate, three-nerved 

 from above the base ; primary veins thick ; secondary veins, two or 

 three pairs, distant from each other, and also from the primary nerves, 

 all branching outside with subdivisions or veinlets entering the teeth ; 

 nervilles in right angle to the veins, llexuous, simple, or branching in 

 the middle ; areolation obsolete. 



This fine leaf, about five centimeters long (the point is broken), four 

 centimeters broad in its widest part, below the middle, is so remarkably 

 similar by its form, the denticulate borders, and the nervation, to Grevi- 

 opsis orhiculata, Sap. (Sezane Fl., p. 411, PI. XI, figs. 11 and 12), that its 

 generic identity is positive. It specifically differs by its larger size, the 

 more distant veins, and the double ramification of the primary nerves. 

 This ramification is more distinct and more generally multiple, the 

 branches forking before reaching the borders and curving along them. 

 The leaf has, like those of the European species, a subbasilar marginal 

 veiulet, which follows the borders, and is united by nervilles in right 

 angle to the primary lateral nerves above. 



Habitat. — Point of Eocks, Wni. Cleburn. 



29. Ehus membranacea, sp. nov. 



Leaves small, membranaceous, thickish, oblong, obtusely-pointed, 

 rounded or subtruncate at base, irregularly coarsely duplicato-dentate ; 

 lateral veins open, the lowest decurving to the middle nerve, craspedo- 

 drome, more or less ramified. 



