z. 
ae 
C. fa 
vy 
< 
‘ yo 
Tm iy ae 1a : : ‘ 
1 , - 
4 4 a “ i ry 
rm i a* — el act ’ 
“a 
nal 









z A] 
a % ~ 
ae cee Aas 
Ess aes 
7 ieee 
a 
194 . ee N. ry BOUNDARY. iousmsiee 




; been alluded to; and that examined in the course of my ‘own exp c 
aii is fully fibsctited in another par! of this Report. As this junct 


ws it may be adduced, Though j in some localities, as at Bittecs eek 
7m separation between the universally recognized Cretaceous, and b 
belonging to the Lignite formation, may not be clearly definable, t 
very seldom wath case. ae te the locally variable charac 




hatte pi tame te and appearance, over the whole western area a of. ; 


interior region, as well as in the typical eastern sections. Pa eon. 
tologically; it is to a great extent a continuation upward of No. 4, and | 
changes it presents! as compared with that division, are mostly th ; 
necessarilly brought about by the shoaling of the waters of th °. 
sea. There also appears to be, in many localities, a second zone of 










Ms sandstone at about this level in the series, which has sometimes nec 

attached by observers to the base of the Lignite formation, and sometime o: 
to No. 5, and to which Prof. Lesquereux has drawn particular a | 

It is characterized by the abundance of fucoidal remains in many a 













where he has examined it. It is not always easy to decide at once a 
between these sandstones, and those more closely attached to i ; 
summit of the Cretaceous, nor does the division appear to be one of ys 
| a great importance, as there is no real physical, or great palontologeal 
2 break. In the valley of the Yellowstone, Dr. Hayden describes, “a 
deep reddish-yellow Sandstone resting on the well marked Cretaceous — 
ae rocks which I cannot positively affirm as belon ging to the upper part of 
ss No. 5, or to the lower bed of the Tertiary.” A similar bed is found =: 
holding the same position, high up on the Missouri, and round the rim of 
a 
a : 
ae 
a the soe ne where it skirts — Black amps ioe near 
stone, enecnly Qe ey or whitish, a jeanee biases in strachanaiel “4 
as overlying Cretaceous No. 4; and this according to Lesquereux forms : 
all round the mountains, the base of the Lignitic formation. These sand- — 
stones are also described south of the Raton Pass, along the base of the ) . 
Rocky Mountains by Dr, Leconte, as “ formed like an immense terrace, | ie: 
which extends as far south as the valley of the Torejo, and perhaps even Or f a 
the North bank of the Cimarron.” + In the valley of the Arkansas, Dr. 
Hayden mentions as resting on No. 5, a “ thick bed of rusty- -yellow: es oA: 

* Geological Report Yellowstone and Missouri Expedition, p. 58. 
t See Lesquereux U. 8. Geol. Surv, Territ., 1872. p. 321. 

