56 
Transactions Texas Academy of Science. 
Cummins, W. F. 
mations over the entire field; so much so that one 'becoming fapiiliar with 
the characteristios of a stratum in one place need have little trouble in 
recognizing it elsewhere when found. 
‘‘The strata of the Paleozoic group as observed along the route have a 
general and uniform dip to the north and northwest, with little or no dis- 
turbance, except in one or two instances, which are noted. The Mesozoic 
strata, on the contrary, have a general inclination to the southeast. 
“Few evidences of faults or folds of the strata in any of the formations 
were seen, exceipt when they are in contact with the eruptive rocks. The 
alternations of limestone, sandstone, and shales in the various formations 
show that the periods of their deposition were attended with alternating 
conditions of subsidence and elevation. 
“The rocks of the Cretaceous system are found in contact with strata 
of both the Carboniferous and 'Silurian, . showing that the 'Silurian and 
Carboniferous strata had been tilted to the northwest before the Creta- 
ceous period; and as the Cretaceous is found 'on or in contact with every 
stratum of the Carboniferous and Permian, from the highest to the lowest, 
there is little doubt that the Cretaceous strata at one time extended con- 
tinuously from the foot of the 'Staked Plains to the Cretaceous beds on the 
east, and that the -present exposure of the underlying Paleozoic group 
is due to their subsequent erosion. 
“The Cretaceous formation of this part of the State belongs entirely to 
the Lower or Comanche series. The beds have a thickness of about 200 
feet wherever seen, except on the upper South Concho river, where the 
thickness increases to about 400 feet.’” 'Pp. 145-146. 
“The Carboniferous system extends over the largest part of the country 
examined during 'this trip, and to it the mO'St of the time was devoted. 
“'No attempt is here made to separate the iSubcarboniferous from the 
Carboniferous, dn fact, I am not certain that the Subcarboniferous for- 
mation occurs. The strata of the entire series, so far as I observed them, 
are conformable, and the fossils found in the lower part of the formation 
were not characteristic of the -Subcarboniferous, but are those which are 
for the most part embraced in the fauna of the coal measures. I am cer- 
tain, however, that there is a section at least 400 feet thick, lower than 
the strata of the coal 'measures which are found in the northern part of 
the 'State. 
“The Permian formation was clearly distinguished overlying the coal 
measures on the west. 
“The general dip of the strata of this system is to the northwest at about 
30 feet to the mile, except near Lampasas, where the dip is to the northeast, 
which may be accounted for either by the existence of an anticlinal in the 
western part of Lampasas county, or possibly by faulting, 
“The strata of the Carboniferous are composed of limestones, sandstones, 
clay beds, and shales with three or more beds of coal. On top of the 
measures in many places is a bed of conglomerate similar to that found 
overlying the coal measures in the northern part of the iState. 
“The measures are about 1600 feet thick, so far as examined, although 
their Uipper part was not reached, lln many places the strata are so 
deeply covered up with drift that it was imipossible to get a continuous 
