22 
(8) Dark grey, dolomitic limestone 91 feet 
(a) Dark grey, weathering brownish 26 feet 
(b ) Dark grey, the lower part very dark. The upper part contains prom- 
inent calcite veins 65 feet 
(9) Light grey, dolomitic limestone with many black chert nodules. The 
lowest bed is conspicuous for its great number of small white quartz geodes. 
Many blocks of this limestone lie loose upon the western slope of mount Aylmer. 28 feet 
(10) Light grey, dolomitic limestone 42 feet 
(a) Rock light grey, fine grained above, coarse grained below 12 feet 
(b) Rock light grey, containing, except in the upper 3 feet, an abundance 
of chert nodules 30 feet 
The uppermost 3-foot bed contains very many specimens of Hapsi- 
phyllum calcareforme and apparently no other species. Below this there is 
an abundance of Lithostrotion pennsylvanicum. These coral heads are 
abundant upon the western slope of mount Aylmer, 50 to 100 feet from the 
summit. The trail passes up this slope. 
This locality is correlated with section 1, locality 24, and section 2, 
locality 6. 
Section 8a 
A brief section, somewhat farther down the slope of mount Aylmer 
than section 3, was made in order to include some very fossiliferous beds. 
Bundle Limestone (Upper Part) (Lower Pennsylvanian) 
(1) Limestone weathering brownish 50 feet 
(2) Grey, rather shaly limestone, weathering reddish brown 20 feet 
No fossils noted. 
(3) Dark grey limestone, in alternately solid and shaly beds 60 feet 
Here occurs an abundance of Triptophyllum minnewankensis. 
(4) Dark grey limestone, a cherty, medium-grained variety alternating with 
a chert-free, coarse-grained variety 20 feet 
The chert is parallel with the bedding plane and occurs both in bands 
1 to 3 inches thick with parallel banding, and as irregular concretions vary- 
ing from a fraction of an inch to several feet in length. The large con- 
cretions are usually in contact by one or more of their offshoots with 
neighbouring concretions; this gives to the weathered surface a very 
uneven appearance, as the limestone enclosed by these chert masses weath- 
ers much more rapidly than the chert. 
The chert-bearing beds are conspicuous for their numerous heads of 
Lithostrotion pennsylvanicum; these are especially abundant in the basal 
bed. The chert-free, coarsely-granular beds contain very few fossils. 
(5) Grey dolomite 120 feet 
(a) Medium grained, with few chert nodules 20 feet 
Fossils few. 
(b) Medium grained, with much chert 20 feet 
(c) Coarse grained. No chert 30 feet 
A few fossils noted. 
(d) Medium grained 20 feet 
No fossils seen. 
(e ) Fine grained, with much chert in both thin bands and nodules, altern- 
ating with chert-free, fine-grained beds. The latter are conspicuous for 
their fracturing across the bedding plane 30 feet 
No fossils noted. 
(6) Dark grey, medium-grained dolomite, alternating with a lighter grey, 
fine-grained dolomite, all fracturing across the bedding plane. A few chert nodules 
present. Crossbedding is common. The basal foot is a light grey quartzite which 
maintains a rather uniform thickness along the strike and is bounded above and 
below by a fine-grained dolomite 40 feet 
