400 E W. Hilgard—Geological History of the Gulf of Mexico. 
ferous to the Bluff or Loess. Thus, in northeastern Texas, they 
have been accounted of Tertiary age; the “ Tertiary iron ores” 
of that region being precisely the same as those of the “ Orange 
Sand” of Louisiana and Mississippi. The same is doubtless 
ore banks” of Tennessee, 
ington and Baltimore. I ascertained its wide prevalence in the 
States of Mississippi, Louisiana and Texas, and identified with 
it the superficial beds observed by Owen in Arkansas and 
southwestern Kentucky, and by Safford in Tennessee. So close 
and cogent a connection was thus established between it and the 
“modified Drift” of the Northwest, that I can no longer doubt 
Its equivalence, whatever may be the precise mode of origi? 
assigned to it. The “Eastern gravel” streams observed by 
Safford in the mountains of Tennessee, and no less by Kerr 
_ North Carolina, have their counterparts in the rivers of Texas, 
and in the great pebble-belts of the Mississippi embayment. 
But it will be difficult to combine into a harmonious whole 
the widely differing observations and opinions of geologists 0? 
the vexed Drift question, unless some agreement is come to 8 
to the precise meaning of the word. Let it be understood that 
F 
oO 
i 
B 
° 
Fry 
Rig’ 
® 
4 
5B 
& 
ra) 
= 
continent, outside of river channels, and that within this “” 
are : 
ms, the Glaciet- 
drift or moraines; t I Een cht ial’) drift f the North- 
atone Se eaten glacial”) =) “fit of 
ai 
