DESCRIPTIONS OF SPECIES. 97 



changes of the incalculable interval now form the most conspicuous ele- 

 ments in our existing forests. 



Formation and locality: Cretaceous (Dakota group). Blackbird Hill, 

 Nebraska. 



Order BERBERIDACE/E. 

 Berberis simplex Newb. 

 PL LVI, fig. 2. 

 Proe. U. S. Nat. Mus., Vol. V (March 21, 1883), p. 514. 



"Leaves pinnate, with three or more pans of leaflets; leaflets ovoid, 

 rounded or emarginate at base, acute, with two to four large spiny teeth on 

 each side." 



Collected by Rev. Thomas Condon. 



This, so far as known, is the first example of the occurrence of a 

 Berberis in the fossil state in America, and of this we have only a single 

 specimen, though that is unmistakable in its character. It is evidently allied 

 to B. aquifolium, which grows so abundantly in the region where the fossil 

 was found, but differs from it in the small number and large size of the teeth 

 on the margins of the leaflets in the fossil. It is true that occasionally the 

 smaller variety of B. aquifolium (B. repens Lind.) has leaflets very much like 

 these, and I have before me as I write a specimen which I collected at 

 Lake City, Colorado, in which some of the leaflets are almost precisely like 

 these, differing from the fossil only in the less prolonged acute apex, and 

 the narrower, somewhat wedge-shaped base. The surface of the fossil is 

 quite smooth, showing almost nothing of the details of nervation; and this 

 in a rock where the finer nerve markings are often most beautifully shown, 

 as in the leaf represented on the same plate and which was obtained from 

 the same beds. Hence we may conclude that in texture the leaf was thicker 

 and its surface smoother than in B. aquifolium, in which the strong reticu- 

 lated nervation is distinctly shown on both sides In some specimens of 

 B. Nepaulensis from the Himalayas we find a closer resemblance to the fossil 

 plant than is offered by any of our native species, viz, sessile and slightly 

 cordate leaflets with a simpler nervation, showing on the under side only the 

 midrib and a basal pair of branches; teeth three to five on each side, the 

 point produced as in the fossil. 



Formation and locality: Tertiary (Miocene). Bridge Creek, Oregon. 



mon xxxv 7 



