Notes on Cincinnatian Fossil Types 
295 
Whitewater division of the Richmond, as identified on Manitoulin 
island. 
Lambe (1899, Canadian Pal. Corals, pt. 1, p. 43) regards the 
Richmond specimens of Calapoecia from all of these localities as 
identical with Calapoecia canadensis, a form described by Billings 
(1865, Canadian Naturalist, vol. 2, p. 426) from the “Black River 
limestone near Ottawa.’' Here it was collected at the Paquette 
Rapids, on the Ottawa river. The Black River specimens of Cala- 
poecia appear to have thinner corallite walls, the arrangement of 
the pores along horizontal lines appears more conspicuous, and the 
denticulations along the septal ridges appear more conspicuous, 
but Lambe is probably correct in failing to find any constant dif- 
ferences, of sufficient importance to be regarded as specific, be- 
tween the Richmond and Black River forms. If it be desired to 
distinguish the Richmond forms from the latter, the term Cala- 
poecia huronensis must be employed. 
8. Tetradium Ontario, Hall 
188 Jf.. Tetradium Ontario Hall, 35th Rep. New York State Mus. Nat. Hist., Plate 16, 
Fig. 9. (Figured but not described) 
1888. Tetradium approximatum Ulrich, Amer. Geol., 1, p. 183 (Nomen nudum) 
1915. Tetradium approximatum Bassler, Bibl. Index Am. Ord. and Sil. Fossils, 
Bull. 92, 2, U. S. Nat. Mus., p. 126Jf (Numerous references to literature and 
published illustrations) 
An excellent illustration of a cross section of Tetradium Ontario, 
showing the form of the corallites in a very satisfactory manner, 
was published by Hall on a plate intended to illustrate the value of 
translucent sections in the study of corals. The origin of the speci- 
men is cited as “Clinton group, shore of lake Ontario,” but the 
specimen was an erratic one, colored reddish, derived from the basal 
part of the red Queenston clay shales north of the western end of 
Lake Ontario. Specimens of Tetradium Ontario occur in situ at 
this horizon at the exposures along the small creek northeast of 
Oakville, about 20 miles southwest of Toronto, in the province of 
Ontario, in Canada, and it is evidently from this province that the 
tjrpe was obtained. The horizon at Oakville corresponds approxi- 
mately to the base of the Coral zone at Streetsville, on the river 
Credit, about 10 miles directly north of Oakville. This horizon 
forms the base of those Canadian strata at present correlated with 
