GEOLOGICAL SUEVEY OF THE TEEEITOEIES. 289 



7. Medicine Bow Coal-Beds. 



rine-grained, grayish shale, separating in horizontal layers ; remains 

 of plants distinct. 



Phragmites Oeningensis, Heer. A fine stem, with articulations, 

 scars of branches, &c. 



PopuLUS LATiOK var. CORDIFOLIA, Al. Br. The same form as that 

 from Alaska, in Heer's Fl. Al., p, 25, PL ii. Fig. 4. 



PopuLUS AECTiCA, Hecr. Same form as in Fl. Arc, I, PI. v, Fig. 11. 



Platanus Guillelm^, Gopp. As in Heer's Fl. Arc, II, PI. xlvii, 

 Fig. 3 ; a species represented by our specimens in many of its varieties! 



Platanus Hatdenii, Newby., (PI. xx. Fig. 1, ined.) The form of this 

 leaf is like that of Platanus heterophylla, Newby., in PI. xxi, Fig. 1, ined., 

 with the same nervation also ; but it has the obtuse, large teeth of P. 

 Haydenii ; the leaf is, however, much smaller j may be referable to 

 Platanus Guillelmw. 



8. Green Eiver Group, high on Hills from Eiver. 



Coarse-grained, yellow, hard limestone shale, with few remains of 

 plants. 



Ceanothus ci^namomoides, sp. nov. Leaf narrowly elliptical, 

 pointed to the base, distinctly and distantly crenulate upward from 

 above the base ; medial nerve slightly thicker than the lateral ones 

 which ascend from the base of the leaf, and nearly parallel to the borders 

 to apparently to three-fourths of the leaf, which is obliquely broken above 

 the middle. The medial nerve has no trace of secondary veins as high 

 as it is discernible, but merely strong, nearly horizontal nervilles, very 

 distinct, like the netting of the areolation ; much like Ceanothus Zizi- 

 plioides, Ung., chloris especially as figured by Heer, (Fl. Ter. Helvc, 

 PI. cxxii, Fig. 25.) It differs by the borders, more distantly crenulate 

 in the upper part only, and by the base of the leaf, which is entire and 

 does not pass downward beyond the point of divergence of the lateral 

 veins. 



Carta Heerii, Etting. A few fragments of leaves of this species, 

 especially of ihe form and nervation marked in Fl. Ter. Helv., PI. xcix, 

 Fig. 23, a. 



9. Junction Station, Suioiit of Hills, near Divide, north op 



Snake Eiver. 



Hard silicified limestone. 



Platanus Guillelmw, Gopp. 



PopuLUS arctica, Heer. Both represented by mere fragments. 



10. Point of Eocks Station, Union Pacific Eailroad. 



Brown ferruginous clay, with small fragments of plants, mostly unde- 

 terminable. 



Cyperites. Numerous fragments heaped in various directions, refer- 

 able to Cyperus Deiicalionis, Heer ; C. Cliavanetisis, Heer ; and C. angus- 

 tior, Heer. (?) None distinct enough for identification. 



Fagus Antipopii, Heer, (Fl. Alas., p. 30, PI. vii. Fig. 4 to 8.) An 



apparently ovate, long-pointed leaf, with straight, nearly parallel, slightly 



diverging, oblique secondary veins. These are simply craspedodrome, 



and the point where they reach the borders is marked by very small 



19 G S 



