LAMOE. ] CANADIAN PALAEOZOIC CORALS. 127 



septal costfe are very distinctly defined at the base but become more flat- 

 tened and obscure upwards. In external characters it resembles A. exilis, 

 but the much greater development of the septa distinguishes it therefrom.' 

 (Billings.) 



" This species is regarded by the present writer as belonging to the genus 

 Zaphrentis on account of its well developed septa ; it appears to differ 

 from Z. gigantea, Lesueur, principally in being more slender, in having 

 fewer septa and in being typically more strongly annulated. In the type 

 specimen a longitudinal section through the cup shows complete, slightly 

 concave tabulae stretching across the visceral chamber from wall to wall 

 and abruptly turned down at their edges. 



" The types of Z. invenusta, Z. Egeria and Z. subrecta are believed to 

 be identical with Z. mirabilis, and to the same species are assigned a 

 number of other specimens in the collection that possess the slender form 

 and the comparatively few septa that are characteristic of the species. 



" Using the type specimen as a basis Z. mirabilis may be described as 

 follows : — ■ 



" Corallum simple, long, cylindrical, slender, pointed at the base, gene- 

 rally curved or variously twisted, ending above in a moderately deep cut 

 with thin vertical side walls and a flat or slightly undulating bottom ; 

 reaching a length of a foot or more and apparently not exceeding between 

 four and five cent, in diameter. Septa of two sizes, alternating, the pri- 

 maries somewhat flexuous, reaching generally rather more than half way 

 to the centre, the secondaries somewhat variable in their length, being in 

 different specimens from less than one-third to about three-fourths as long 

 as the primaries ; numbering in all from about sixty to one hundred. 

 On the surface of the corallum the position of the outer ends of the septa 

 is indicated by distinct, shallow, longitudinal furrows. Tabulae complete, 

 numerous, flat or undulating, turned down at the edges. A small septal 

 fovea is generally discernible near the lateral margin on one side of the 

 convex curve." (Lambe, 1899.) 



Localities and formation. — Corniferous limestone of Ontario. The type 

 specimen is from lot 14, concession 1, Oneida township, county of Haldi- 

 mand, collected by E. DeCew in 1857 ; another and larger specimen is 

 from lot 31, concession 4, Cayuga township, county of Haldimand and 

 was also collected by E. DeCew. 



