DEVONIAN ROCKS OF CANADA WEST. 



Ill 



*' "We have provisionally admitted as forming distinct species, va- 

 rious ramose Favosites whicli have previously been described as such 

 by Blainville, but wHcb may probably, when better known, be found 

 to be only varieties of the same species. Such are F. reticulata, F. 

 cervicornis, and F. duiia. The latter differs, however, from the first, 

 by its branches not being coalescent, nor so closely set, and by the 

 calices being rounded and obliquely placed on the surface of the 

 branches. F. cervicornis has its calices more unequal in size, its 

 walls thinner, and its branches longer and more irregular. All these 

 have only a single line of pores on each side of the walls, and these 

 pores are large, and placed at a distance from each other." 



These authors have recognised F. duhia among specimens from 

 Ohio; and in Canada all the forms represented in the European books 

 occur. The branches occur of all sizes from four lines to one inch 

 and a half in diameter. The walls of the corallites are oftenf so 

 greatly thickened that the apertures are distant from each other as 

 in figures 11 and 12, which resembles F. duiia of Blainville, and the 



Figs. 10, 11, 12. — Three forms of i^. polymorpha from the eorniferous limestone, 



Canada West. 



variety F. gracilis of Goldfuss. Pine reticulated masses may be 

 procured along the shores of Lake Erie near Port Colborne. The 

 other forms are not uncommon wherever there is a large exposure of 

 the eorniferous limestone in Canada "West. Although I have placed 

 F. cervicornis separately, yet I am not satisfied that it is a distinct 

 species. 



Genus Michelinia. — (De Koninck.) 



Generic Characters, — " Corallum compound, forming rounded, or 

 conoidal masses of inseparably united, thick- walled, polygonal tubes 



