353 



allied to each other ^ and future discoveries may prove them to be identical. 

 It occurs at Oxford with A. Salteri. 



Bathyurus amplimaryinatus (fig. 241, a) has been found only at the 

 Mingan Islands in the Calciferous. 



B. conicus (fig. 241, V) was originally discovered at St. Timothy, on 

 the Beauharnois Canal, in the upper part of the Calciferous. It occurs 

 also at Comstock's Landing, in the State of New York, in the same forma- 

 tion. A specimen, only distinguishable from this species by having the 

 surface smooth instead of tuberculated, was collected in the Quebec group 

 at Cow Head, Newfoundland, in Division P. In all these three localities 

 it occurs associated with Camarilla calcifera, the most characteristic 

 brachiopod of the Point Levis limestone. 



B. Cybele occurs at the Mingan Islands, Beauharnois, and in the 

 Counties of Leeds and Grenville. It has been found also at Orwell, in 

 the State of Vermont, and at Comstock's Landing, in New York. 



BATHYURUS MINGANENSIS. 



Description. Glabella rather strongly convex, sub-conical, sides in the 

 posterior two-thirds of the length straight and nearly parallel, the anterior 

 third converging so as to form a rather narrowly rounded apex. Neck 

 segment large ; neck furrow all across. Fixed cheeks moderately promi- 

 nent. The eye appears to be semicircular ; the posterior angle on a line cross- 

 ing the glabella at almost the mid-length and three lines from the dorsal 

 furrow. From the posterior angle the eye seems to curve forwards and 

 inwards, so that its anterior angle is close to the side of the glabella. The 

 pygidium, of which only a fragment has been collected, has at least four 

 wide rings on the axis. It has also four, and perhaps more segments, in 

 the side lobes. These segments, in the side lobes, are wide and flat, 

 with an obscure groove along the middle . The margin of the pygidium is 

 unknown. 



Length of the glabella 9 lines ; width at the mid-length 7 lines. The 

 pygidium is apparently about 15 lines in length. 



This species is founded on an imperfect glabella and part of a pygidium, 

 of which however sufficient is preserved to show that it is distinct from 

 any described form. It is most nearly related to B. amplimarginatus, 

 but has the glabella broader and the ribs of the side lobes divided by a 

 furrow along the middle. 



Locality and Formation. Mingan Islands ; Calciferous formation. 

 Collector. J. Richardson. 



