Fig. 
Fig. 
PLATE I. 
Srromatopora ostiouata, Nich, A fragment of the natural size, from the 
Guelph Formation. Introduced for comparison. 
. Portion of the same, enlarged, showing the oscula on the surface. 
STROMATOPORA TUBERCULATA, Nich. A fragment of the natural size. (p. 14.) 
. Section of a portion of the same, enlarged. 
STROMATOPORA GRANULATA, Nich. A fragment of the natural size. (p. 16.) 
. Section of a portion of the same, enlarged. 
STROMATOPORA MAMMILLATA, Nich. A fragment of the natural size. (p. 17.) 
