NOTES ON THE FOSSILS OF ONTARIO. - 139 



and close-set. Septa distinct but rudimentary, only extending a 

 short distance into the theca, about twelve in number in each 

 corallite^ 



Cannapora annulata is closely allied to C. junciformis, Hall, from 

 the horizon of the Clinton Group. The latter species, however, 

 has the mural expansions placed at intervals of about a tenth of an 

 inch apart ; so that there are only ten in the space of an inch, instead 

 of between forty and fifty, as in the present species. Our examples, 

 also, do not appear to have attained anything like the dimensions of 

 C, junciformis, the corallites rarely exceeding half an inch in height. 



Locality and Formation. — -Niagara Limestone, Owen Sound. 



54. Syeingopora retiformis, Billings. {Ref. Canadian Naturalist, 

 Vol. ITI., p. 424). This beautiful ^species is of common occurrence, 

 and attains a large size in the Niagara Limestone of Owen Sound. 

 Specimens often show the radiating septa very distinctly, much more 

 so than is usually the case in this genus. 



55. Zaphrentis Rcemeri, Edw. and H. Niagara Limestone, 

 Owen Sound. 



56. Zaphrentis Stokesi, Edw. and H. Niagara Limestone, 

 Owen Sound. 



57. Zaphrentis (Ganini a) bilateralis, Hall. Niagara Limestone 

 Owen Sound and Niagara River. 



58. Cystiphyllum VESIGULOSUM, Goldfuss. Transverse sections of a 

 Cystiphylluvi, probably referable to this species, are not uncommon 

 in the Niagara Limestone at Thorold. 



59. Petraia pygm^a, Billings. Niagara Limestone, Thorold. 



60. DiPHYPHYLLUM (diplophyllum) CiESPiTosuM, Hall. Common 

 in the Niagara Limestone at Thorold. 



6L Caryocrinus ornatus, Hail. Niagara Limestone, Thorold 

 and Niagara River. 



62. Dictyonema gracile. Hall. Niagara Limestone, Hamilton. 



63. Clathropora frondosa. Hall. It seems certain that Prof. 

 Hall has included under this name two quite distinct species. The 

 one which we have met with in the Niagara Limestone has the frond 

 perforated with rounded perforations of comparatively small size. 

 {See Pal. N.Y., Vol. II., pi. Ix., B., fig 5&). The perforations are 

 not more than from half a line to three-fifths of a line in diameter. 



