DESCRirXlON OF SPECIES— CURNE/E. 243 



the Lower Ligiiitic of Golden iuul Evaiisloii. One has been described by 

 Dr. Newberry from numerous s})ecitnens Ibund in the Lignilieof the Yellow- 

 stone River. Tiiey are all more or less intimately related to sjiecies of our 

 time. The Upper Tertiary or I'liocene of California has two very fine Cornus, 

 more closely allied to present ^i)ecies of the Pacific coast. They constitute 

 four per cent, of the whole flora known from that formation, indicating a 

 marked preponderance of the genus in llu; more recent formations. The 

 leaves of Cornus are easily recognized by their ovate, generally acuminate 

 I'orm, and by ihe direction of Ihe upper lateral veins, curving inside and 

 tending toward the point. 



Co I'll us sii bo 1* bi f c ra, sp. uov. 

 IMatd XLII, Fig. 2. 

 ComuB orbifera (Heer), Lesqx., Annual Report, 1873, p. 402. 



Leaves oval, rounded upward, and also rounded or truncate to a short petiole, entire; lateral 

 nerves on au open angle of divergence, much curved in traversing the areas ;nerville8 strong, ohlique, 

 with cross-veinlets in right atigle, forming loose, irregularly square meshes. 



I had considered this leaf as identical with C. orbifera, Heer (Fl. Tert. 

 ITelv., iii, ix 27, pi. cv, figs. 15-17); but Count Saporta, who has published 

 a leaf of the sarae species (£t., iii, p. 97, pi. xiii, fig. 3), has compared ours 

 with European specimens, and considers it different. The lateral veins are not 

 quite as regular in distance in the American leaf, and the nervilles are slightly 

 more oldique. It is, however, difficult to positively note the essential char- 

 acters of a species from a mere fragment like this ; the upper part being 

 destroyed, and the real form being therefore uncertain. 



Habitat. — Golden, Colorado. 



Cornus impress a, Lesqx. 



Plate XLII, Figs. 3. 



Cornus impressa, Lesqx., Annual Report, 1873, p. 408. 



Leaves coriaceous, entire, regularly oval, rounded to a very short, scarcely distinct acumen, 

 rounded also in narrowing to the base; secondary nerves at an acute angle of divergence, canipto.lrome 

 and aerodrome. 



This leaf, evidently coriaceous, its outlines being deeply impressed into 

 the stone, is also, l)ut more distantly, related to C. orbifera. The secondary 

 nerves, all simple, joined by strong nervilles, more distant and less oblique 

 than in the former sjjccies, pass up from the strong midrib in an angle of 

 divergence of about 40°, scarcely curve in traversing the areas, follow the 

 borders by a series of simple bows, anastomosing by the nervilles. The 



