356 Fossils of the Calciferous Sandrock. 



side at about one fourth the heighth. In full-grown specimens 

 there is an obscure carina on the body whorl, one fourth of a line 

 above the spiral band, and another close to the suture ; the space 

 between these two carinas is flat or slightly concave ; half a line 

 below the band there is a third carina, scarcely visible, and below 

 this the whorl is rounded veutricose. There is a small umbilicus. 

 Length of shell, four lines ; greatest width, two lines and a half. 

 Surface minutely striated. 



Locality and formation. — St. Anns and near St. Eustache, 

 extremely abundant, Calciferous sandrock. 



Collectors. — A Murray, J. Richardson. 



Trochonema tricarinata. (N. s.) 



Description. — Depressed turbinate ; whorls, four ; with three 

 carinas, two of which are on the outer edge of the body whorl, 

 and of these one is lost in the suture above. The third carina 

 is on the upper side of the whorl, about the middle, but rather 

 nearer the suture than the outer edge. The spaces between the 

 carinas, are concave; base depressed convex not carinated. — 

 Width of only specimen collected, nine lines. 



At first sight this species appears to be the widely known T. 

 umbilicata, (Hall) but differs therefrom by having only three 

 carinas. 



Locality and formation. — MinganIslands,Calciferous sandrock. 



Collectors. — Sir W. E. Logan, J. Richardson. 



Ophileta compacta. (Salter). 



0. Compacta. (Salter). Canadian Fossils Decade, 1, p. 16, pi. 3. 

 This species occurs near Beauharnois, near the Village of St. 

 Eustache, and also at Romain's Island. 



Helicotoma uniangulata. (Hall.) 



Euomphalus uniangulatus. (Hall). PalaeonU, iV". Y., vol. 1, 



p. 9, pi. 3, fig. 1, 1 a. 

 Occurs at Romain's Island. 



Helicotoma perstriata. (N. s.) 



Description. — One inch and a half wide ; whorls, three or four, 

 with a strong carina on the upper side near the suture, another 

 near the outer margin, and, apparently, several smaller ones be- 

 low on the outside of the outer volution. The spaces between 



