297 







AMPYX SEMICOSTATUS. (N. sp.) 



Fig. 287. 



Description. Pygidium sub-triangular, posterior margin broadly 

 rounded, obtusely angular at the apex ; length two-fifths of the width ; 

 axis cylindro-conical, strongly convex, extending the whole length, with 

 five or six distinctly defined rounded annulations ; dorsal furrows on each 

 side of the axis, deep and well defined. The side lobes are rather tumid 

 in the middle, but concave towards the margin, the latter with a distinctly 

 elevated angular rim and nearly vertically bevelled ; there are five or six 

 ribs extending about half-way from the margin to the axis. In very small 

 specimens only two or three are visible. 



Locality and Formation. N, Table Head and Pistolet Bay ; P, four 

 miles N. E. from Portland Creek, Newfoundland ; Quebec group. 



Collector. J. Richardson. 



AGNOSTUS GALBA. (N. sp.) 



Fig. 288. Fig. 289. 



Fig. 288. Agnostus Galba. Enlarged about two diameters. 

 289. A. Fabiiis. Enlarged two diameters. 



Description. Head strongly convex, with a narrow rim ; front margin 

 rounded ; glabella convex, well defined all round, strongly elevated above 

 the general surface, smooth, no tubercle nor furrows ; in some specimens 

 a slight indentation on each side at about the mid-length ; a small trian- 

 gular lobe on each side at the posterior margin. The proportional length 

 of the glabella varies slightly, but it is, in general, about two-thirds of the 

 whole length of the head. 



Pygidium, in contour and convexity, like the head. Axis strongly 

 convex, well defined all round by the dorsal furrows ; a furrow runs all 

 across at one-third the length from the apex ; a short one on each side at 

 two-thirds the length from the apex. The tubercle forms a longitudinal 

 medium lobe in the anterior two-thirds of the axis. It (the tubercle) is, 

 at the anterior margin, slightly elevated above the general convexity of 

 the axis ; it is less elevated just over the anterior of pair furrows ; but, 

 behind this point, it rises to twice the height, and terminates abruptly at 



U 



