68 EXPLORATION OF THE COUNTRY BETWEEN 
tends over an area of two hundred and fifty miles in length and fifty 
to sixty in breadth. 
2. The great Lignite basin, commencing on the Missouri river near 
the mouth of Cannon Ball river, and reaching to the mouth of Muscle- 
shell river, a distance of nearly eight hundred miles ina straight 
line, extends up the Yellowstone six or seven hundred miles ; ite 
limits in that direction not known. In the summer of 1854, I traced 
it to the mouth of the Big Horn river, and obtained through the 
Crow Indians undoubted Tertiary fossils from a point two hundred 
miles further up the river, Its. boundaries haye not yet been deter- 
mined, but may be estimated to cover an area, with very little inter- 
ruption, of from four to six thousand square miles. 
3. The ‘‘Bad Lands of the Judith,’’ which seems to be a dis- 
tinct. basin, probably an estuary deposite, the exact age of which is 
not determined, covers an area of about 40 miles in length, and 10 to 
20 in breadth. The details of the geology of these systems I have 
reserved for a succeeding report, wit 
e whole region watered by the Missouri also presents many z00- 
logical and botanical characteristics which are peculiar, and even in 
its ancient fauna and flora, it exhibits forms and types found in no 
other geological district. “ag 
‘is: uri to the confluence of the Platte, the 
timber along the river i overy abundant and luxuriant, and the up- 
ot : 
by the annual decay of the enormous growth 
_ The forest ees from Council Bluffs to Dorion’s Hills, consist mostl 
of cottonwood, black walnut, butternut, ash, ‘American and red sla 
