272 
PALEONTOLOGICAL GEOLOGY 
that the faunas of the Grand Tower limestone and those of the 
Callaway limestone are not nearly so distinct as is now assumed. 
Admission by those, who have always upheld a Paleozoic Ozark 
Isle, that “The presence of a Grand Tower outlier at Rolla indi¬ 
cates much greater submergence of the Ozark Uplift [region] 
during Onondaga time than has commonly been supposed,” now 
reduces the premised Devonic land area of the Ozark tract to a 
few inconsequential peaks known as the St. Francois Mountains. 
But why especially exempt these little porphyry peaks? Their 
tops are only 600 feet above the level of the upland plains surface 
at Rolla, and 800 feet above their own bases. Surely these De¬ 
vonic limestones are not laid down in less than 100 fathoms of 
water! Physiographers all agree that more than 1,000 feet of 
rocks are removed from the Ozark area in very late geological 
times, during the Tertic peneplanation alone for that matter. 
Thus, the St. Francois Peaks really owe their present supremacy 
to their relatively hard granitic and porphyritic substructures. 
What is now needed before all else, with the adequate collec¬ 
tions of well-preserved organic remains at last at hand ,is refined 
adjustment of the Grand Tower section of east Missouri to the 
Callaway limestone of the central part of the State. Professor 
Weller’s extensive accumulations of fossils from the former, 
D. K. Greger’s fine suites from the latter, and the Rolla specimens 
from between should give us the long longed for desiderata. 
Keyes. 
