32 CONTRIBUTIONS TO CANADIAN PAL^ONTOLOGV. 



ridges occupies the side nearest the axis of the stem or branch and is 

 opposed by the remaining two on the side toward the exterior. 



A certain amount of variation is noticeable in different specimens, and 

 in parts of the same specimen, in the obliquity of the calyces to the surface; 

 in the lower parts of the corallum especially, the corallites are apt to emerge 

 more nearly at right angles to the surface. That this species is at times 

 reticulated, is borne out by a specimen presumably belonging to this species, 

 in which frequent coalescence of the branches is observable. In some 

 specimens many of the calyces are closed by opercula. 



In only a few of the specimens are the longitudinal ridges apparent, the 

 corallites being as a rule either filled with matrix or quite empty with 

 smooth sides. The tabulse and squamulse are seen in longitudinal sections, 

 whilst the pores are preserved in most of the specimens. The wearing or 

 weathering of the surface, with the destruction of the lips of the calyces, 

 brings to light the subcircular or polygonal outlines of the individual 

 corallites, a feature not seen when the surface is entire. 



In a specimen of C. cryptodens, in which the tooth-like ridges are pre. 

 served near the mouths of the corallites, striations are seen on the walls 

 of the calyces, as in Striatopora Jormosa. These two species are strikingly 

 similar in outward form and the discovery in the formerof acharacterwhich 

 was relied on for their specific as well as generic separation, can scarcely 

 leave any doubt as to their being conspecific. The calicular striations are 

 not seen except in weathered specimens and may represent septal ridges 

 or grooves only partially developed, or possibly are the result of the unequal 

 weathering of the wall substance of the corallites. The specimen of C. 

 cryptodens referred to was obtained in the Corniferous limestone at 

 Rama's Farm, Port Colborne, Ont., by E. Billings in 1857. 



This, species occurs in the Corniferous limestone of Ontario and in the 

 Devonian formation on the Red Deer River, Lake Winnipegosis ; it has 

 also been collected from Devonian rocks at the Long Portage, Missinaibi 

 River, and on the Albany River. 



Cladopoba labiosa, Billings. (Sp.) 



Alveolites labiosa, Billings. 1859. Canadian Journal, new ceries, vol. IV., p. 104, figs. 



14 and 15. 

 Cladopora prolifica, Hall and Whitfield. 1873. Twenty-third Report N.Y. State 



Museum of Nat. Hist., p. 230, pi. 10, fig. 2. 

 Alveolites labiosa, Nicholson. 1874. Palaeon. of Ont., p. 63, fig. 12. 

 Alveolites Billingsi, Nicholson. 1874. Ibid, p. 55, fig. 14c. 



Cladopora labiosa, Rominger. 1876. Geol. Sur. Mich., Foss. Corals, p. 51, pi, 

 XXI., fig. 2. 



