No. 2 .] NICHOLSON — NEW FOSSILS. 143 



shales. All these, except H. tenuiseptatum, have come under 

 my notice as occurring in the Cornif'erous Limestone of Western 

 Ontario, and I have also a single new form to record. 



III. Heliophyllum Colbornense, n. sp. 



Corallum simple, cylindrical, not expanding towards the cup. 

 Septa sixty at a diameter of one inch, carrying on their flat 

 surfaces arched stria) at distances of from one-third to half a 

 line. Epitheca with numerous rounded or sharp-edged annula- 

 tions and constrictions of growth. A flat space at the bottom of 

 the cup, to the centre of which the septa extend. Cup deep; 

 fossette unknown. 



This species is nearly related to H. Caijugaensc and H. Cana- 

 dense, Billings ; but it is, I think, decidedly distinct. It is 

 distinguished from H. Canadense by its cylindrical and not 

 broadly-expanding shape, the cup being equal to or even less 

 than the diameter of the coral at a point apparently a little 

 above the base ; by the flattening of the bottom of the calice ; 

 by the greater- closeness of the arched septal stri^: and by the 

 smaller number of septa. From H. Cai/ugaense the present 

 species is separated by its much smaller thickness, its cylindrical, 

 not expanding form, the smaller number of the septa, and the 

 closeness of the septal striae. 



The length of //. Colbornense must have been over three or 

 four inches; but none of my specimens are perfect. The di- 

 mensions of a broken individual are : length two inches and a- 

 half; diameter of broken base one inch; diameter of cup ten 

 lines ; depth of cup four lines. In another also broken specimen, 

 the length is two inches and a quarter ; the diameter at the 

 broken base thirteen lines ; the diameter of the cup one inch ; 

 and the depth of the cup five lines. Other examples referable 

 to this species exhibit a diameter of from an inch and a quarter 

 to an inch and a half. 



Locality and Formation. — Corniferous limestone of Port Col- 

 borne. 



IV. Petraia (?) LoGANi, n. sp. 



Corallum small, turbinate, more or less curved, almost trigonal 

 in transverse section, owing to its being flattened on the side of 

 the convex curvature, and also on the lateral surfaces. Septa 

 twenty-six or twenty-eight at a point a little above the base, but 

 sixty or more at the margin of the calice, the increase of number 



