lambe] CANADIAN PALAEOZOIC CORALS. 27 



Ccenites appears to be most nearly related to Cladopora, from which it 

 is distinguished by the shape of the calyces and by the sudden, not 

 gradual, thickening of the walls of the corallites at the surface. The 

 corallites are at first prostrate, when the corallum has the form of a thin 

 expansion, but when it is dendroid they are almost upright in the centre 

 of the branch or stem. The calyces are transversely elongated and may 

 be straight or curved. 



Ccenites juniperina, Eichwald. 



Ccenites juniperinus, Eichwald. 1829. Zoolog. speciale, t. I., p. 197. 



Limaria clathrata, Lonsdale. 1839. Murch. Sil. Sys., p. 692, pi. 16 bis, figs. 7, 7 a, 7 b.. 



Ccenites juniperinus, Milne-Edwards and Haime. 1851. Polyp. Foss. des Terr. Palaeoz., 



p. 301. 

 Limaria ramulosa, Hall. 1852. Palaeon. New York, vol. II., p. 142, pi. XXXIX., 



figs. 4a — d. 

 Ccenites juniperinus, Milne-Edwards and Haime. 1855. Brit. Foss. Corals, p. 276, pi. 



LXV., figs. 4, 4a. 

 Alveolites repens, Billings. 1863. Rep. of Progress, Geol. Survey of Canada, p. 323. 

 Alveolites Niagarensis, Nicholson and Hinde. 1874. Canadian Journal, new series,, 



vol. XIV., p. 152 and 1875, Palaeon. of Ont., p. 56, fig. 27. 

 Limaria ramulosa, Rominger. 1876. Geol. Sur. Mich., Foss. Corals, p. 43. 

 Ccenites juniperinus, Nicholson. 1879. Palaeoz. Tab. Corals, p. 134, pi. VI., figs. 5, 5 6. 



" Corallum dendroid, of cylindrical dichotomously-dividing branches, 

 the diameter of which is generally about two lines. Corallites nearly 

 vertical in the centre of the branches, with thin walls, and about one- 

 sixth of a line in diameter ; gradually diverging in their upward course 

 till they reach a point from one-quarter to half a line from the surface, 

 when they suddenly bend outwards, their walls being now greatly 

 thickened, and the visceral chamber reduced to a mere slit. Calices 

 fissure-like and elongated in the direction of the transverse diameter of 

 the branches, their long diameter about one-third of aline; the lower 

 margin adorned with two prominent teeth, while the upper margin carries 

 a single tooth corresponding in position to the notch between the lower 

 teeth. Tabulae not very numerous, but well developed and complete. 

 Mural pores moderately numerous, circular, not excessively large, 

 irregularly distributed." (Nicholson.) 



A number of fragments, from 1 to 2 inches long, of a dendroid 

 coral with cylindrical branches, about 4 mm. thick, from the Niagara 

 formation at Thorold, Ont., are referred to this species. In longitudinal 

 sections the structure is seen to be similar to that described by Nicholson ; 

 the thickening of the walls of the corallites when they bend abruptly 

 outward near the surface, and the mural pores and tabulae are clearly seen. 

 Transverse sections show that a prominent longitudinal ridge occupies the 



