546 L.. Lesquereux—Lignitic formations of the Rocky Mountains. 
If then, as LeConte’s data seem to show, the final and most 
considerable anticlinal elevation of the great interior range took 
place during the same period that witnessed the great fisssure 
eruptions of the Coast and Cascade ranges, it may not be un- 
reasonable to suppose these events to have not only been con- 
temporaneous, but to have borne to each other something of 
the relation of cause and effect: and that each of the numerous 
superimposed strata of igneous rock in the latter region may 
represent, not only the direct effect zn loco of more or less par- 
oxysmal thrusts, but also the reflex action of the simultaneously 
progressing anticlinals in the high Sierras. 
Art. LI.—On the Age of the Lignitic formations of the Rocky 
Mountains ; by L. LESQUEREUX. 
Pror. J. S. Newberry has published, in a former number of 
this Journal (On the Ingnites and Plant-Beds of Western Amer- 
@ ist. The flora of the Colorado Lignite-beds has almost nothing in 
common with that of the European Eocene. Its botanical aspect 1s 
point of view he is quite safe in the statement that the Eocene flora 
has not yet been recognized in this country, he adds: that the 
H. 
‘The flora of Shoppey cannot be taken into account for @ 
comparison with the fossil plants of our Lignitic, mostly repre 
i. * Loc cit., p. 400. + Loc cit., p. 402. 
