Silurian and Devonion Fossils of Canada. 427 



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

 tubes of large size, marked internally with numerous vertical, 

 lamellar striae, and communicating pores ; base of cells filled up 

 by very irregular, numerous, highly inclined vesicular plates, not 

 forming distinct horizontal diaphragms ; external or basal epitheca 

 of the general mass, strong, concentrically wrinkled, and some- 

 times spinose." — McCoy, British Palaeozoic Fossiles, page 80. 



This genus differs from Favosites in the vesicular character of 

 the transverse diaphragms, and in the radiating lamellae being 

 represented by vertical striae on the inner surface of the cells 

 instead of series of minute spines. The cells are usually much 

 larger than in Favosites. The genus appears to be confined to 

 the Devonian and Carboniferous formation. 



Michelinia convexa (D'Orbigny). 

 (Prodr. de Paleont., t. 1, p. 101, 1850.) 



Description. — Corallum forming hemispherical, or erect rudely 

 cylindrical masses, several inches in diameter ; the base covered by 

 a strong wrinkled epitheca. Adult calices from four to five lines 

 in diameter ; about forty septal striee in each ; pores small, arrang- 

 ed in several vertical series in some of the tubes, irregularly dis- 

 tributed in others ; distant from half a line to more than one line. 

 Diaphragms very convex in the centre of the tubes, and usually 

 with three or four smaller rounded prominences on their surface ; 

 a vertical section shews that they are more vesicular at the sides 

 of the cells than in the centre, where they are from half a line to 

 one line and a-half distant. 



MM. Edwards and "Haime in their description of this species 

 say that there are two vertical series of pores on the larger plane 

 sides of the cells and one on the smaller. Our specimen, however 

 shews that this is not a constant character.* 



Formation and Locality. — Devonian ; Onondaga and Cornife- 

 rous limestones. Rama's farm, Port Colbome. Savage's quarry, 

 lot 6, con. 1, Wainflect. Oxford, near Woodstock and in nume- 

 rous other localities in Western Canada. This species occurs in 

 Michigan and in Preston County, Virgina. 



MiCHELINIA INTERMITTENS (Billings). 



Description.— Corallum forming large hemispherical masses; 

 calyces nearly equal in diameter, with periodical constrictions 



* See Polypiers Fossiles des Terrains Palteozoiques, page 251. 



