238 UNITED STATES GEOLOGICAL SDKVEY— TEKTIAKY FLORA. 



Habitat. — Mount Brosse, Colorado; leaves with ciilirc lobes ( JV. Mitchell). 

 ElU Creek, near Yellowstone River, ]\rontana (F. C. Sloane, Jos. Savage). 

 Evanston, Wyoming {Prof. F. B. Mcch). Yellow Creek and Mount Brosse, 

 Colorado, \\ itli Cissas lobato-crenata, Laurus Brossiana, etc. {Dr. F. V. Hayden). 

 Not seen at Golden, Colorado, nor at Black Buttes, Wyoming. It appears to 

 be a northern species, or, at least, widely distributed in the North Lignitic. 



AMPELIDE^. 



In this order, I should perhaps consider merely the North American 

 genera Vitis and Ampelopsis, the two species of Cissvs of the present flora 

 being generally described as Vilis; and, indeed, both these genera are united 

 in one by the highest authorities. We have, however, some fossil leaves 

 identical with fossil species described as Cissus by the European paleontolo- 

 gists, and thus have to follow the distinction which they have established. 

 The Cissus species of the present flora are mostly of the tropical and equa- 

 torial regions, especially of India, South America, and the Southern Islands. 

 Per contra, the genus Vitis, in its limitation, has the greatest number of its 

 living representatives in the United States, which, without counting two 

 of Cissus, has eight species of Viiis. One inhabits South America; Asia has 

 seven, and Japan two. The origin of the Grape, so widely cultivated in 

 Europe, is apparently unknown. From the historical records of its use, 

 it ought to be placed in Asia. Anyhow, we find the two genera Cissus and 

 Vitis represented in the European Tertiary, the first by fifteen species, two 

 of which are Eocene, and the second by eleven, which all are Miocene. In 

 this country, we may, it seems, refer the origin of the group to the Creta- 

 ceous, for Prof Heer, in his Phyllites da Nebraska, has described as Cissites 

 a leaf which he considers as more distinctly representing a species of the 

 Ampelideoi than that of any other family of plants; and, from the same for- 

 mation of the Dakota group, I have referred to the same order nine species, 

 following, for this determination, the opinion of Count Saporta. And as we 

 have, in the Lower Lignitic Eocene, leaves and seeds evidently representing 

 Cissus and Vitis, this old origin is thus apparently confirmed. 



Cissus Ia;vigata, Lesqx. 



Plato XL, Figs. 12, l:!. 



Cissus IcBvigata, Lesqx., Annual Report, 1872, p. 380. — Schp., V<Sg<St. Pal., iii, p. 602. 



Leaves membraDaceous, with a smooth or polished surface, broadly oval iu outline, nanowed in 

 a round curve to the petiole ; borders entire. 



The two leaves representing this species liave the upper part destroyed. 



