227 



■width, exposing all the -whorls to the apex. Aperture rhomboidal ; outer 

 lip conforming to the slope of the spire ; lower lip straight and nearly 

 horizontal on the outside, rounded at, the inner angle ; inner lip gently 

 convex or straight, forming an obtuse angle with the lower. Surface 

 finely striated. 



This species belongs to the type of P. Ramsayi, from which it is at 

 once distinguished by the wider umbilicus. It is more closely allied to 

 P. Ampliitrite (see p. 32), differing therefrom in being smaller, and in 

 having a groove near the suture. 



Width at the base of largest specimen (a fragment) 2 i nches ; height 

 a little less than the width. 



Locality and Formation. — G, Cape Norman, H, Ta le Head, New- 

 foundland ; Quebec group. 



Collector. — J. llichardson. 



Plburotomaria Hortensia. (N. sp.) 



Fig. 211. 



Descrip 'itn. — Shell discoidal, with a sharp projecting margin having a 

 concave bar-d- just within the edge, both above and below. Spire de- 

 pressed conical with a rounded apex. Whorls in the upper two-thirds of 

 their width gently convex, becoming more flattened on approaching the 

 concave band ; the apical whorl convex its whole width. On the under 

 side the whorls grow gradually more convex from without inwards, most 

 tumid at two-thirds their -width, thence rather abruptly rounded into the 

 umbilicus, which is scarcely one-third the whole width. 



The specimen consists of two whorls, and is probably the apical portion 

 of a larger indi-vidual. Its width is 4i hues ; height 3 lines. The margin 

 is at about half the whole height. 



Closely allied to P. Harpya, but has a smaller umbilicus. 



Locality and Formation. — H, Table Head, Newfoundland ; Quebec 

 group. 



Collector. — J. llichardson. 



Pleueotomaria Harpya. (N. sp.) 



Description. — Lenticular, whorls wide, depressed convex both above 

 and below ; umbilicus one-half the whole width. 



This species is founded on a specimen which is a cast of the interior. 

 Width 28 lines ; height about 7 lines. There are three -\vhorls, allowing 

 for a small one 2 lines across in the centre. The other two increase from 

 a width of IJ lines to 9 lines in making two turns. A vertical polished 



