294 
Aug. F. Foerste 
Cincinnatian areas, the corallites occasionally attain a diameter 
of 3 millimeters, but more commonly average between 2 and 2.3 
millimeters. The tabulae rarely are well preserved; sometimes 
only the marginal parts, where attached to the walls of the coral- 
lites, are retained, but usually the tabulae have been entirely re- 
moved by weathering. About 7 to 10 tabulae occur in a length 
of 5 millimeters, occasionally increasing to 12 in this distance. The 
denticulate projections along the crest of the septal ridges rarely 
are well preserved. Judging from the small size of the figured type 
it is probable that it was obtained somewhere in Clinton or neigh- 
boring counties, in Ohio, where specimens are rare, and usually quite 
small. 
The Canadian cotypes of Columnopora cribriformis, obtained, 
according to Nicholson “In the Hudson River Group, River Credit, 
Ontario (collected by Dr. G. J. Hinde),’’ were found at Streetsville, 
about 17 miles west of the center of Toronto. From Streetsville 
Junction a road leads northeast to the Credit river, and Calapoecia 
occurs west of the bridge, along the northern side of the river. The 
horizon corresponds approximately to the Whitewater as exposed 
in Ohio and Indiana. The Canadian cotypes from the Credit river 
were destroyed by the fire which burned up the Museum of the 
University of Toronto, years ago. 
Both the Ohio and Credit river cotypes of Columnopora crihri- 
formis evidently are specifically identical with Calapoecia huronensis^ 
described by Billings (1865, Canadian Naturalist, volume 2, page 
426) from the “Hudson River formation. Cape Smyth, Lake Huron. 
Cape Smith forms the most eastern part of Manitoulin island. The 
Richmond exposures occur at the Clay Cliff, about 4 miles south of 
the extremity of the cape. Here, as well as at numerous other 
localities on Manitoulin island, Calapoecia huronensis occurs both 
in strata corresponding to the Waynesville member as well as in 
those correlated with the Whitewater member of the Richmond. 
Houghtonia huronica, described by Rominger (1876, Geol. 
Surv. Michigan, vol. 3, pt. 2, p. 18) from the “Hudson River group 
of Drummond’s island, associated with Columnaria stellata,” also 
is identical with Calapoecia huronensis. On Drummond island the 
Richmond exposures form the extreme northern margin of the 
island, extending in an east and west direction for about 5 miles. 
The specimens described by Rominger probably were obtained from 
strata corresponding to the Coral zone, in the lower part of the 
