242 The Ottawa Naturalist. [March 



within. Septa numbering from about thirty-two to thirty-eight 

 in average sized coralHtes, alternately long and short, the longer 

 passing to the centre, the shorter reaching about half-way. Curv- 

 ed dissepiments in the outer part of the interseptal spaces in a 

 single or at times apparently in a double series. Tabulae close- 

 set, about twenty in a space of 5 mm., deflected downward at 

 their margins, difficult to make out in the silicified specimens 

 examined. Epitheca well developed, shewing faint annular 

 markings and longitudinal septal lines. 



The corallites of this species are more slender than those of 

 the preceding and the septa are less numerous. 



Locality and formation. — Grand Manitoulin Island, Laice 

 Huron, collected by Alexander Murray in 1847; also by R. Bell 

 and H. G. Vennor, 1865 ; by J. Townsend, 1883 and by R. Bell, 

 1891 ; Niagara formation. 



Rominger mentions its occurrence in the Niagara rocks of 

 Point Detour, Lake Huron. 



DiPHYPHYLLUM SIMCOENSE, Billings, sp. 



Eridophyltum Simcoense, Billings. 1859. Canad. Journ. vol., IV. 



new series, p. 132, fig. 27. 

 DiphyphyUum stramineum, Billings. 1859. Ibid, p. 135. 



•' stramineuni, Nicholson 1874. Rep. Palaeont. 



Prov. Ontario, p. 33, pi. V,fig. 6 



Eridophyllurn Simcoense, Nicholson. 1874 Ibid, p. 34, pi. VI, fig. 5. 

 Dlp!iyphyllu})i Simcoense, Rominger. 1876 Geo). Surv. Michigan, 

 Fossil Corals, p. 122, pi. XLVI, figs. 3 and 4. 



Ainplexus or Diphyphyllujn, Whiteaves, 1892. Geol. Surv. 

 Canada, Contr. Canad. Palaeont., vol. i.pt.iv, p 270, pi. xxxv, 

 figs. 2, 2a. 



Corallum bushy, composed of flexuous, cylindrical corallites 

 radiating upward from a small basal beginning and rapidly 

 increasing by lateral budding so as to form colonies at times 25 

 cent, high and equally broad. Corallites varying in diameter 





