219 



is variable. Usually the ventral valve is depressed convex, the outline 

 forming an even, flattened arch, from beak to front, but often it is strongly 

 arched and angulated about the middle. The carination of the umbo 

 sometimes extends quite to the front margin, and in such instances it has a 

 strong angular elevated stria along its crest in the median line of the shell. 

 Width from 7 lines to 1 inch. Length from to the width. 



A separated dorsal valve, apparently belonging to this species, has the 

 divaricator process undivided, as in the genus Orthis. 



Locality and Formation. K, L, M, N, Point Rich and Table Head, 

 N, Burnt Cape, Pistolet Bay ; P, four miles north-east from Portland 

 Creek, Newfoundland ; Quebec group. 



Collector. J. Richardson. 



OTHER SPECIES OF STROPHOMENA AND LEPMNA. 



1. Strophomena imbecilis. Subquadrate or semi-elliptical, about half 

 an inch wide, with extremely fine radiating striae. The specimens are all 

 imperfect, but show that this is a new species. P, four miles north-east 

 from Portland Creek. 



2. Leptcena decipiens ? Ante, p. 73, a single valve not distinguishable 

 from this species, was found in P, four miles north-east from Portland 

 Creek. 



CAMERELLA PARVA. (N. sp.) 



Description. Shell small, ovate, length about one-third greater than 

 the width; apical angle about 60 ; sides gently convex; front broadly 

 rounded. Ventral valve rather strongly convex, uniformly arched from 

 beak to front ; mesial groove narrow, concave in the bottom, dying out at 

 two-thirds the length from the front. Dorsal valve broad, ovate, not so 

 long as the ventral, and more uniformly but not so strongly convex ; mesial 

 fold narrow, rounded, dying out at about half the length. Surface appa- 

 rently smooth. Length of ventral valve about 2 lines. 



The specimens are imperfect. The beak of the ventral valve is not well 

 exposed, but seems to be strongly incurved. 



Locality and Formation. N, Table Head ; P, four miles north-east 

 from Portland Creek, Newfoundland. 



Collector. J. Richardson. 



