349 



tlon, close to the shell, there is no doubt. Closely resembles 0. arcuoli- 

 ratum (Hall) of the Trenton, but that species has a small central siphuncle. 



Locality and Formation. From a rock-cutting in the Brockville and 

 Ottawa Railway in the Township of Kitley ; Calciferous formation. 



Collector. The specimen figured was procured from Mr. Francis 

 Ballantyne, of the Township of Kitley. 



ORTHOCERAS INDAGATOR. (N. sp.) 



Description. This species is founded on some detached siphuncles 

 retaining the marks of the septa, but no other parts. The best preserved 

 specimen is three and a half inches in length, six lines in diameter at the 

 smaller extremity, and about seven lines at the larger. Thirty-one septal 

 rings. It appears to be flattened on one side as if by contact with the 

 shell. 



Another specimen, three inches in length, six lines in diameter at the 

 larger, and four at the smaller, has twenty-seven septal rings. 



This species resembles 0. Flavins (ante, p. 255), but has the septa 

 somewhat more distant. The spaces between the septa are also more 

 concave, and, in one of the specimens, are transversely marked with several 

 thread-like rough rings, which are not seen at all in the 0. Flavins. 



Locality and Formation. Mingan Islands ; Calciferous formation. 



Collectors. Sir W. E. Logan, J. Richardson. 



ORTHOCERAS EDAX. (N. sp.) 



Description. Siphuncle the same as that of 0. Misnsqnoi (ante, 

 p. 314), but with more distant septa. One specimen four inches in length 

 tapers from nine lines to five lines, or at the rate of one line to the inch. 

 Where the diameter is between six and seven lines there are four septal 

 rings to the inch. They are most distant from the apex on the side of the 

 concave curve, shewing that the position of the siphuncle is similar to that 

 of 0. Mistisqnoi. The curvature is very slight, the height of the arch 

 formed by it being only two lines in a length of four inches. 



It is barely possible that this may be a variety of the 0. Missisqnoi, but 

 owing to the very great difference in the distance of the septal rings, I 

 think it best to give it a separate name. 



Locality and Formation. Township of Oxford ; Calciferous formation. 



Collector.R. Billings. 



