i88 . The American Geologist. September, 1901. 
Brachiopods predominate, with the larg-e and robust Atrypa 
reticularis at the head. Gypidula rumingeri Uall and Clarke is 
also extremely abundant, while the Stropheodontas and Spir- 
ifers are common, and represented by all the common and 
some rare species. Chonetes, Productella, and other char- 
acteristic Hamiltonian brachiopods occur abundantly. Among- 
corals the smaller types predominate, i e., Aulopora, Ceratopora 
etc. In the lower beds, however, the reef-building types occur, 
notably Acervularia. Stromatoporoids are also, though more 
rarely met with. 
Loc. 15. This is along the shore of Bm-nham bay, south- 
west of Presque Isle. No outcrops are found here, but the 
beach is composed of rounded and subangular dark to light 
gray lim|estone pebbles. Chert is a common constituent of this 
rock, which probably belongs to the Dundee formation (repre- 
senting- the Corniferous limestone). 
Loc. 16. This is in front of Presque Isle light, along the 
shore of lake Huron. A dark, somewhat shaly, apparently 
non-fossiliferous limestone crops out at the w'ater's edge. This 
undoubtedly is the lower Dundee limestone (stratum 19) which 
probably forms the shore for a considerable portion of the 
county. 
Loc. ly. This is on the mainland, north of Presque Isle. 
The rock, thoug-h locally disturbed, chiefly by shore ice, is un- 
doubtedly in place, and represents the stratum overlying that 
which crops out in front of Presque Isle light. The rock is a 
very compact and uniform grained limestone, of a drab color, 
and sparingly fossiliferous. Almost the only fossil found in 
it was a large and rather smooth Paracyclas. 
Loc. 18. This is on the farm land north of the county line 
and east of the line of the section. The outcrop is in line with 
those of Loc. 14, and of the same type, containing- also the same 
species of fossils. 
Loc. ip. This is at the sink holes north of the Presque 
Isle county line, and east of the line of the section. The rock 
exposed in the walls of these sinks is as follows : 
FEET 
Fine grained limestone, of a very compact texture 12 
Shale, bituminous at top, but becoming more calcareous down- 
ward, with fossils of the Hamilton types — 
