WILLIAMS AND 
KINDLE. 
CORRELATION OF CERTAIN SECTIONS. 131 
The three sections on the right represent a single measured set of 
beds near one another. The gap which is covered in the valley of 
Towanda Creek is estimated from the dip of the beds on each side, so 
that it is believed the total length of the section is approximately 
correct. In this section 1,487 feet are referred to the Chemung for- 
mation, the Chemung species prevailing to the top. The top of the 
Franklindale calcareous beds is 400 feet down in the Chemung, and its 
thickness is 160 feet in the Gulf Brook section (zones 75 to 58). From 
the top of the Chemung to an arbitrary line drawn between the Cat- 
taraugus and Oswayo (at 1455 C8) is 653 feet; this is the estimated 
thickness of the Cattaraugus for this section. 
The correlation of the Towanda Narrows section (1456 A) with the 
Gulf Brook (Leroy) section (1455 A) is made by means of the upper 
calcareous zone of the Franklindale limestone beds — 1456 A17 and 
20, being correlated with 1455 A 73 and 75. As both of these sec- 
tions are based on detailed measurements of the individual zones, this 
places zone 1456 A40, which contains an unmistakable Chemung fau- 
nule, a little over 1,700 feet above zone 1455 A8, which also holds a dis- 
tinctly Chemung faunule, and over 250 (top 263) feet above the arbitrary 
line drawn at top of the Chemung formation. This arbitrary line is 
drawn as being approximately the place of beginning of typical Cats- 
kill red sedimentation; below, for several hundred feet, appear occa- 
sionally dull reddish and purplish beds, but no considerable bright red 
sandstones. It is not imagined that this upper zone of Chemung 
species, 1456 A40, is in reality the highest place of occurrence of this 
fauna. Further search will be likely to show species of this fauna as 
long as the marine conditions w r ere persistent in the neighborhood of 
this section. The stopping of the marine Chemung invertebrates is 
supposed to have been occasioned by a change of local conditions 
which was associated with deposition of the red beds, and locally drove 
out the species from the region, but did not destroy them. This inter- 
pretation seems best to explain the irregularity of the line of separation 
between Chemung and Cattaraugus. 
The interval between the top of zone 1456 A40 of the Towanda Nar- 
rows section and the observed base of the South Mountain section on 
the opposite side of the Towanda Creek Valley is estimated to be about 
100 feet. The rocks are all covered and the estimate is based on dip 
and actual barometric determination of altitude of the several outcrops. 
This estimate may be too great or too little, but the measuresments 
of the sections otherwise are based upon actual distances from zone to 
zone as measured at the outcrops. 
The red beds prevail in the observed outcrops from the base of the 
South Mountain section to zone 1455 C26, which is correlated with the 
Armenia limestone lentil of the section on Armenia Mountain (145S 
B29). Nevertheless, as Kindle states on a previous page, the red 
