299 



Differs from both A. Galha and A, Americanus in the form of the 

 tubercle on the axis of the pygidium, and also in not having the glabella 

 defined all round by the dorsal furrows, as it is in the two species com- 

 pared. 



The different individuals differ somewhat in the amount of the convexity. 



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

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



Collector. — J. Richardson. 



ENTOMOSTRACA. 



Leperditia turgida. (N. sp.) 



Description. — Small and strongly convex ; dorsal margin straight ; 

 anterior and posterior dorsal angles obliquely truncated at an angle of 

 about 45°, and for nearly half the breadth ; ventral margin most convex in 

 the posterior two-thirds, thence gently convex and sloping upwards. The 

 greatest breadth is a little behind the mid-length. The right valve is 

 strongly convex, most inflated in the posterior two- thirds, and nearer the 

 ventral than the dorsal margin. Left valve smaller and less convex than 

 the right. 



Length of the largest and most perfect right valve observed, 2 lines ; 

 breadth of the same, a little behind the mid-length, 1§ lines. Numerous 

 specimens of all sizes, from the length of J a line up to 2 lines, occur on 

 the same slabs. The smaller ones are more nearly ovate than the larger. 



This species has a general resemblance to L. Canaden&is (Jones), but 

 is always more tumid, and can be distinguished therefrom, after having 

 been studied, at a glance. 



Locality and Formation. — G and H, Port aux Choix and Cape Nor- 

 man, Newfoundland ; Quebec group. 



Collector. — J. Richardson. 



« 



Leperditia concinnula. (N. sp.) 



Description. — Rather small, ovate, dorsal margin straight ; anterior 

 extremity rounded and slightly narrower than the posterior ; the latter 

 more broadly rounded, obliquely truncated at the dorsal angle, whei*o, 

 also, there is a short spine or projection situated on the angle. The 

 ventral margin is somewhat straight, sub-parallel with the dorsal, but 

 slightly converging towards the anterior extremity. At both extremities 

 the margin of both valves is compressed and sometimes seen to have a 



