222 



margin. If a line be drawn between the most projecting points of the 

 anterior and posterior extremities, it will divide the shell into two nearly 

 equal parts : of these, the upper or dorsal half is triangular, the umbones 

 forming the apex with an angle of about 120, the posterior slope a little 

 longer than the anterior : the ventral half of the shell is semi-ovate, the 

 anterior end the largest. The shell is very thick, and rather strongly con- 

 vex. Surface with obscure concentric striae. Transverse length 8 lines ; 

 umbones to ventral margin 5 lines. 



Ctenodonta contracta (Salter) has the posterior extremity more pointed, 

 but in no other respect differs from this species. 



Locality and Formation. M, Table Head, Newfoundland ; Quebec 

 group. 



Collector. J. Richardson. 



GASTEROPODA. 



HOLOPEA OPHELIA. (N. sp.) 



Fig. 204. 

 Pig. 204. Holopea Ophelia. Different views of the same specimen. 



Description. Shell small, turbinate, apical angle between 80 and 90; 

 whorls three, including a minute one at the apex, smoothly ventricose, 

 most prominent at about the lower third. Aperture sub-ovate, the outer 

 lip broadly convex, the inner lip, from the umbilicus downwards, slightly 

 curved, and folded over the minute umbilicus ; the upper and inner half 

 of the aperture formed by the penultimate whorl . 



Length 6 lines ; width, from the outer lip through, about the same ; 

 height of the aperture, 4 lines. On a posterior view the two apical 

 whorls constitute only one-fifth the whole length. The last whorl forms 

 nearly the whole bulk. 



Li some of the specimens there seems to be a spiral band about the mid- 

 dle of the whorl, as in Pleurotomaria. 



Locality and Formation. L, Point Rich, Newfoundland ; Quebec 

 group. 



Collector. J. Richardson. 



