38 1 



METOPTOMA NYCTEIS. (N. sp.) 



Fig. 39. 



Description. Ovate, uniformly rounded posteriorly, sides gently convex, 

 anterior extremity more narrowly rounded than the posterior. On a side 

 view the greatest elevation is at about one-third or one-fourth the whole 

 length from the apex; the latter small, acutely rounded, a little over- 

 hanging the base and depressed below the greatest elevation about three- 

 sevenths the whole height of the shell. From the most prominent point 

 the outline is gently and uniformly curved to the front margin, from the 

 same point descending with a shorter curve to the apex. 



Length at the base, from 12 to 16 lines ; greatest width a little behind 

 the middle, from 9 to 12 lines ; greatest elevation, from 5 to 7 lines ; height 

 of apex above base, 3 or 4 lines. Surface unknown. 



Locality and Formation. Mingan Islands. In the upper part of the 

 Calciferous formation. 



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



METOPTOMA EUBULE. (N. sp.) 



Description. Ovate, posterior margin broadly rounded, greatest width 

 at about one third or one fourth the length from the posterior margin, 

 from which point the sides are somewhat straight and converging so as to 

 form an obtuse angle of about 110 at the apex. The shell is rather 

 strongly convex, most elevated in the middle or a little behind the middle 

 and the apex incurved nearly down to the plane of the lateral margin. 

 Surface only imperfectly known, apparently marked with somewhat rugose 

 concentric lines of growth. Length 13 lines ; width 14 lines ; height 7 

 lines. 



This species resembles M. Nycteis, but is comparatively much broader 

 behind, and has the apex not so much elevated. 



Locality and Formation. Phillipsburgh, in the County of Missisquoi, 

 Canada East. Upper part of the limestone. In beds holding fossils 

 approaching in aspect to those of the Chazy or Black River limestone. 



Collector. P. J. Farnsworth. 



METOPTOMA. OEITHYIA. (N. sp.) 



Fig. 40. 



Description. Acutely conical, apex much elevated, base ovate, the 

 margin broadly rounded anteriorly, sides in the anterior half gently round- 

 ed, in the posterior half slightly concave and the posterior margin narrowly 

 rounded. The outline in a side view is subtriangular, the apex a little in 



