42 CONTHIBUTIONS TO CANADIAN PALEONTOLOGY. 



upper ends, or is not as well defined there as at the sides and below. The 

 calyces average 1-5 mm. in height or length and 1 mm. in width, those of 

 a row being at a distance from each other about equal to their length, and 

 the rows themselves are at varying distances apart proportionate to the 

 thickness of the stems or branches. The size of the calyces is about the 

 same in large as in small stems. The surface between the calyces is deli- 

 cately sculptured longitudinally by interrupted, generally wavy strise. 



In longitudinal sections, short, slightly curved corallites are seen to 

 pass upward and outward from an imaginary axial line to the surface, the 

 calyces pointing slightly upward. The corallites on opposite sides of the 

 axial line are at the same height and alternate with those of the other 

 rows ; this alternation is seen in longitudinal sections and is continued in 

 the arrangement of the calyces at the surface. In the centre of the stems 

 the corallites are small, about -5 mm. or less in width, subpolygonal, with 

 thin walls, which rapidly grow thicker toward the surface. After the 

 walls become thick all trace of the boundaries of contiguous corallites, as 

 far as can be learned by transverse and longitudinal sections, is lost ; and 

 no indications of them are seen on the surface. Mural pores, small, few 

 in number, confined apparently to those parts of the corallites where the 

 walls are not excessively thickened. Tabulse few in number, complete, 

 directly transverse. It is noticed that when the stems are flattened on 

 four sides the rows of calyces occur on the angles. No septa or strise are 

 seen, in longitudinal or transverse sections, in the interior of the corallites, 

 but near the edges of the calyces obscure striations are observed passing 

 out over the raised margins in a radial direction. 



Devonian. — Hamilton formation ; not uncommon at Thedford, Ont. 



Genus Calapcecia, Billings. 1865. 



(Canadian Naturalist, new series, vol. IT., p. 425.) 



Corallum massive, composed of rather equal, polygonal, subpolygonal 

 or circular corallites either in contact and polygonal or distant and cir- 

 cular ; walls of corallites of moderate thickness, amalgamated when in 

 juxtaposition ; pores so numerous as to reduce the walls to a mere lattice- 

 work, forming regular longitudinal and horizontal rows ; spiniferous 

 septal ridges about twenty in number, between the longitudinal rows of 

 pores and passing out over the slightly exsert edges of the calyces ; tabulae 

 complete, horizontal, often with secondary tabulse ; spaces between 

 corallites crossed by irregular horizontal diaphragms. 



