272 

 ASAPHUS MORRISII. (N. sp.) 



Fig. 257. 



Description. Large, oblong-ovate. Pjgidium nearly semicircular, 

 length a little greater than half the width ; axis narrow, moderately 

 convex, very distinctly defined by the dorsal furrows, about one-fifth the 

 whole width at the front margin, thence tapering to an obtuse point near 

 the posterior margin, not well defined at the end. There is a smooth con- 

 cave border all round, the width of which is about one-third of the width 

 of the side lobes at the anterior margin. There are about ten obscure 

 rounded rings on the axis ; those in the posterior half of the length being 

 in general scarcely distinguishable. The side lobes have five ribs each 

 besides the half rib at the anterior margin. The length of the axis varies 

 in different individuals from four-fifths to five-sixths the whole length. 

 The anterior angles are strongly facetted. 



The hypostoma is oblong, with two short rounded lobes in front, and a 

 shallow notch between. The muscular impressions are deep, transverse, 

 and situated at one-third the length from the front margin. The posterior 

 two-thirds gently convex. Surface of hypostoma crossed by deep undu- 

 lating striae. 



Width of the largest pygidium seen, 3 inches ; length, 2 J inches. 



Locality and Formation. N, Table Head, P, four miles N. E. from 

 Portland Creek, Newfoundland ; Quebec group. 



Collector. J. Richardson. 



ASAPHUS QUADRATIC AUDATUS. (N. Sp.) 



V 



Fig. 258. 



Description. Obscurely sub-quadrate, the middle two-thirds convex, 

 the outer third gradually becoming flattened or gently concave towards 

 the edge ; anterior margin apparently nearly straight, facetted on the 

 outer third ; angles narrowly rounded ; sides in the anterior half sub- 

 parallel, in the posterior half and angles broadly rounded; posterior 

 margin with the middle-third either straight or gently concave. Axis well 

 defined, stoutly conical, rather convex, a little less than one-third the 

 whole width, and about two-thirds the whole length ; width of the obtusely 

 rounded apex half the width at the front margin. The surface is marked 

 by rather coarse sub-concentric fissure-like striae. On the side lobes there 

 is a single pleural groove at the front margin, and another forming a half 



