1899] Lam BE — Canadian Paleozoic Corals. 243 



from 3 to 6 or 7 mm., frequently roughened by annular swellings 

 of growth and constrictions, covered by an epitheca shewing 

 minor growth markings and longitudinal septal furrows. 

 There is a marked variation in different colonies in the number 

 of horizontal spurs connecting the corallites : in some specimens 

 they are numerous, from about 2 to 4 mm. apart vertically, 

 springing outward from all sides of the corallites, in others they 

 occur at less frequent intervals whilst in some they appear to be 

 almost absent . Septa short, bearing arched carinas on their 

 sides, divisible into two sizes, primaries and secondaries, number- 

 ing in all from about thirty to forty, the primaries seldom reach- 

 ing half way to the centre of the visceral chamber, the second- 

 aries very short, projecting but little inside of the single row of 

 curved dissepiments in the interseptal spaces. In transverse 

 sections of the corallites the dissepiments have the appearance 

 of an inner wall about "5 mm. distant from the wall proper as in 

 the Silurian species D.ccBspitosiaii, Hall. Tabulae well developed, 

 flat, horizontal, bent slightly down at their edges ; from ten to 

 fifteen occurring in a space of 5 mm. 



This species is somewhat similar in inside structure to D. 

 ccespitosuni, Hall from which it differs principally in having 

 shorter and less numerous septa. 



The coral from the Devonian (Stringocephalus zone) of 

 Dawson Bay and vicinity, Lake Winnipegosis. described by 

 Mr. Whiteaves (op. cit. pp.270 and 27i),and mentioned by him 

 as bearing "a remarkably close resemblance in size, shape and 

 internal structure " to " the DipJiyphylluni straniineum of 

 Billings," is here referred to D. Sijncoense with which the writer 

 considers D. stramineum to be conspecific, a view already expres- 

 sed by Dr. Rominger in his excellent work on fossil corals. 



Locality and fonnatton. — Abundant in the Corniferous for- 

 mation of Ontario ; also from the middle Devonian of Lake 

 Winnipegosis. 



Omphyma Eriphyle, Billings, sp. 

 '^Omphytna subttirbinata, Milne-Edwards and Haime. 1855. Brit. 



V 



Foss. Corals, p. 288, pi. LXViil, fig.s. i, i a — c. 



'A 



•v./ 



