152 NOTES ON THE FOSSILS OP ONTARIO. 



of Owen Sound we have obtained several examples of an Alveolites, 

 which in general characters and dimensions resembles A. Fischeri, 

 Billings, of the Corniferous and Hamilton Formations, and which we 

 are unable to separate specifically from this form. The corallum 

 forms a thin laminar expansion about one line in thickness, celluli- 

 ferous on the two sides, and either continuous or rarely partially 

 reticulated. The calices are transversely oval or sub-triangular, 

 usually with one curved and one straight side, sometimes with one 

 curved and two straight sides. The long diameter of the calices is 

 from one-third of a line to half a line, and they are sejDarated from 

 one another by about the same distance. 



Locality and Formation. — Niagara Limestone, Owen Sound. 



51. Alveolites Niagarensis, Nicholson and Hinde. Corallum 

 dendroid, branches cylindrical, about two lines in diameter, dividing 

 dichotomously. Calices small, distinctly triangular, with the apex 

 of the triangle directed downwards, about six in the space of two 

 lines. The upper side of each calice carries a single prominent septal 

 tooth in the form of a vertical plate, which is placed in the median 

 plane of the aperture, dividing it into equal halves and giving it an 

 almost crescentic appearance. 



c 



Fig. 3. — Alveolites JSfiagarmsis, Nich. and Hinde. a, Fragment, of the natural 

 size ; b, Small portion enlarged ; c, Single calice still further enlarged. 



We cannot identify this with any previously recorded form, though 

 it bears a general resemblance to more than one known species. It 

 is most nearly allied to A. labiosa, Billings, from the Corniferous 

 Limestone. ' All the unquestionable examples of the latter which we 

 have examined show, however, no septal teeth at all ; whilst one or 

 two specimens which we have doubtfully referred to A. labiosa, and 

 which possess a single vertical septal ridge on the upper side of the calice, 

 have this ridge placed altogether on one side instead of centrally. 



Locality and Formation. — Niagara Limestone, Rockwood. 

 G^ejiMS ASTRiEOPHYLLUM. ((Nicholson and Hinde.) 



Corallum aggregate, composed of slender cylindrical corallites, 

 united laterally by numerous successive mm-al expansions or hori- 



