346 



MURCHISONIA ADA. (N. sp.) 



Fig. 333. 

 Fig. 333. Murc/iisonia Ada. A gutta percha cast of the exterior. 



Description. Shell small slender with twelve or more whorls. Apical 

 angle between 15 and 20. The whorls are short, there being twelve in 

 a length of nine lines of the apical portion. They are moderately and 

 uniformly convex in the lower two-thirds of their width ; in the upper 

 third with a shallow concave band ; close to the suture an obscure 

 rounded carina which forms the sutural edge. Surface unknown ; but on 

 one of the whorls there appears to be a thread-like spiral carina about the 

 middle of the most convex part. 



Closely allied to M. acrea (ante, p. 231, fig. 216) ; but in that species 

 the lower portion of the whorls is flat. M. Anna is a larger species, with 

 a distinct band just below the middle, and not concave in the upper third. 



Locality and Formation. Counties of Leeds and Grenville ; Calcif- 

 erous formation. 



Collector. E. Billings. 



METOPTOMA SIMPLEX. (N. sp.) 



Fig 334. Fig 335. 



Fig. 334. Metoptoma simplex. Fig. 335. Bellerophon macer. 



Description. Shell small, varying from broad-oval to nearly circular ; 

 height, from one-half to five-sixths of the width ; apex acute, incurved, 

 the point is sometimes nearly over, but usually a little behind, the anterior 

 margin. The most elevated part is just behind the extreme point of the 

 apex, thence to the posterior margin the outline descends with a gently 

 convex slope. The outline beneath the apex is, on a side view, distinctly 

 concave. Length 4 to 7 lines ; width a little less than the length. 



Locality and Formation. Near Mirrickville ; Calciferous formation. 

 Collector. E. Billings. 



