295 



Ampyx l-s:viusculus. (N. sp.) 



Fig. 285. 



Description. — Pygidium triangular, nearly smooth ; axis rather strongly 

 convex, well defined and promment to the apex, crossed by some obscure 

 grooves, which, however, are so indistinct that to a superficial view the 

 surface seems to be quite smooth. The posterior margin is broadly 

 bevelled, sloping at an angle of 45°, the upper angle of the bevel rounded. 

 Side lobes gently convex, smooth, with the exception of a single linear 

 groove close to the anterior margin. 



Width of the largest pygidium collected 5^ lines ; length 2i hues ; 

 width of the axis at the front margin 1| lines ; thickness of the posterior 

 margin or width of the sloping plane of the bevelled edge | of a line. 



This species differs from A. normalis, in having the pygidium propor- 

 tionally wider, a more prominent axis and a thicker posterior margin. 



Locality and Formation. — N, Table Head, Newfoundland; Quebec 

 group. 



Collector. — J. Richardson. 



Ampyx normalis. (N. sp.) 



Fig. 285. 



Fig. 286. 



Fig. 287. 



Fig. 285. — Ampyx Iceviusculus. — A pygidium enlarged one-fourth. 



286. — d. normalis.— The head (witbont the movable cheeks), and the 



pygidium. 

 287. — A. semicostatus, — A pygidium enlarged two diameters. 



Description. — Head, without the movable cheek, triangular, the width 

 about one-third greater than the length ; fixed cheeks, gently convex, 

 smooth ; neck segment consisting of a flat plate, mclining backwards. 

 The glabella elongate-ovate, greatest width about the mid-length, one 

 fourth narrower at the neck segment, the apex extending a httlc over the 

 front margin of the head ; the rostrum, apparently, when perfect, equal to 

 the whole length of the head, not round but fluted ; two or three ovate or 

 nearly circular scars, one each side of the glabella in the posterior half. 



