252 THE ICE AGE IN CANADA. 



spira superne planata, suturis maxime impressis, basi tumente ; 

 umbilico intus majore, extus modico ; apertura sublunata, postice ad 

 angulum circ. 30° inclinatk, antice late rotundata ; labro acuto, postice 

 planato ; labio acuto, planato, baud reflexo ; columella postice regu- 

 lariter arcuata, neque emarginata, nee angulata, nee insculpta. 



Long, (apice decoUato) '82, long. spir. '32, lat. '76 poll. Dii\ 90°. 



Hab. Montreal, in strato glaciali, fossilis, rarissime reperta. Mus. 

 Dawson, McGill Coll., Nat. Hist. Soc. 



Dr. Carpenter adds the following remarks : 



While almost all the other drift fossils are of species still living in 

 the neighbouring seas, this is not known, even generically, to be at 

 present in existence. It is hard to pronounce satisfactorily on its 

 relationships. In its thin, coated shell it resembles Velutina ; the 

 striae and loose whirls recall Naticina ; the straight pillar lip reminds 

 us of Fossarus ; while the umbilicus and rounded base, with entire 

 mouth, best accord with the Natica group. With Trichotropis and its 

 congeners I can see no resemblance. One remarkable feature in all 

 the specimens is the decollation of the upper whirls, seen even in a 

 nearly perfect young specimen, '2 across ; other young specimens, even 

 smaller, have only one whirl and a half remaining. The broken 

 portion is filled up not so much by a septum as by a solid thickening. 

 The separation of the whirls is complete from the beginning ; and 

 although, in the parietal portion, they are closely appressed, the 

 smooth and somewhat glossy epidermis is distinctly seen between. 

 The fracture of the mouth in most of the specimens, enables this 

 feature to be distinctly observed ; and would also reveal the "internal 

 groove " and columellar callosity ascribed to Torellia, did any such 

 exist. 



The straightening of the inner lip, at an angle of 30° from the axis, 

 makes the umbilicus by no means large (for a Naticoid shell) when 

 viewed from the base in the line of the pillar ; but the same cause 

 enlarges it within, recalling the adult appearance of Amphithalamus. 

 The flattening of the upper portion of the whirls gives the shell some- 

 what of an lanthinoid aspect. 



While the analogies of the shell point in so many different directions, 

 it is impossible to assign it even to its family group. It is to be hoped, 

 however, that the dredge will yet reveal its existence in a living state. 



The above species may be supposed to resemble Torellia vestita, 

 Jeffreys, from Norway. Our specimens differ however in form, as 

 above noted, and also in the absence of the tooth in the inner lip, and 

 in the smooth epidermis. 



